Everything 1 Flashcards
(500 cards)
1
Q
What do computers do to data?
A
process it
2
Q
_____ is the basic building block of all computers
A
binary
3
Q
What is a microprocessor?
A
Same role as CPU but smaller scale // usually for a specific task // AKA embedded system // example are traffic lights, digital alarm clocks
4
Q
What’s a CPU?
A
Central processing unit // performs thousands of tasks and complex instructions // example smartphones or laptops
5
Q
What’s von Neumann architecture?
A
CPU access memory directly // memory stores programs and data // programs are series of instructions carried out in order
6
Q
What is the fetch decode execute cycle?
A
Everytime a computer performs a task or runs a program it runs the FDE cycle // Fetches the instruction into the CPU // CPU decodes the instruction // Instruction is executed by CPU
7
Q
What happens in the fetch step of FDE cycle?
A
PC contains address of memory location of next instruction // address is copied from PC to MAR via address bus // instruction at address contained in MAR temporarily copied to MDR using data bus // instruction of MDR copied into CIR // PC incrememts by 1, points to next instruction // instruction gets decoded then executed by signals via control bus to other parts of the computer
8
Q
FETCH - What happens after the PC gets first instruction?
A
Address copied from PC to MAR
9
Q
FETCH - What happens after MAR receives instruction via address bus?
A
Instruction copied to MDR
10
Q
FETCH - Where do instructions go after MDR?
A
CIR
11
Q
When instructions are executed by CPU, what component performs maths and logic calculations?
A
Arithmetic Logic Unit (ALU)
12
Q
What’s the ALU’s special register for storing interim calculations called?
A
Accumulator (ACC)
13
Q
Name 3 types of buses in CPU
A
data bus, control bus, address bus
14
Q
What does the CIR do?
A
stores the current instructions being decoded and executed
15
Q
What does the MAR do? (Memory address register)
A
stores the address of the memory location currently being read from/written to
16
Q
What does the MDR do? (Memory data register)
A
stores data which has just been read from memory/data and is about to be written to memory
17
Q
What does the PC do? (program counter)
A
stores the address where the next instruction to be read can be found
18
Q
What does the CU do? (control unit)
A
sends control signals that manages the execution of instructions in the cpu
19
Q
Describe the address bus
A
Carries addresses throughout the computer (unidirectional)
20
Q
Describe the data bus
A
Alllows data to be sent through the computer (bi-directional)
21
Q
Describe the control bus
A
Carries signals from the control unit to all other components (bi-directional)
22
Q
Another name for RAM is
A
IAS Immediate Access Store
23
Q
Convert 12 to binary?
A
1100
24
Q
Convert 23 to binary
A
10111
25
Convert 43 to binary
101011
26
Convert 62 to binary
111110
27
Convert 15 to binary
1111
28
Convert 8 to binary
1000
29
Convert 0110 to denary
6
30
Convert 01101 to denary
13
31
Convert 101010 to denary
42
32
Convert 11111 to denary
31
33
Convert 1011101 to denary
93
34
Convert 6 to binary
110
35
What are the 8 bit binary placeholders?
128 / 64 / 32 / 16 / 8 / 4 / 2 / 1
36
What are the 12 bit binary placeholders?
2048 / 1024 / 512 / 256 / 128 / 64 / 32 / 16 / 8 / 4 / 2 / 1
37
Hexadecimal is base ___
16
38
Example of a 4 digit Hex number
A23F or 12FF or 79BB etc
39
_________ is base 16
hexadecimal
40
In hexadecimal A to F represent...
A = 10, B = 11, C = 12, D = 13, E = 14, F = 15
41
How to convert hex to denary?
Convert to hex to binary -> binary to denary
42
How to convert denary to hex?
Convert denary to binary -> binary to hex
43
Convert A0 to binary
1010000
44
Convert 1C to binary
0001 1100
45
Convert 50 (hex) to binary
0101 0000
46
Convert AA to binary
10101010
47
Convert A00 to binary
1010 0000 0000
48
Convert 1001 1011 to hex
9B
49
Convert 1100 1010 to hex
CA
50
What does the system clock do?
Defines the clock cycle that synchronises all computer operations
51
Which bus transmits timing signals ensuring sychronisation?
Control bus
52
What defines the clock cycle that synchronises all computer operations?
System clock
53
What happens if you increase clock speed?
Processing speed is also increased - but NOT NECESSARILY overall performance
54
3.5 Ghz is equivalent to
3.5 billion clock cycles per second
55
What hardware factors improve overall performance of a computer?
Number of cores, size of cache and speed of clock can affect performance of CPU
56
How do you increase processor speed (but not necessarily overall performance)?
Increase clock speed
57
What happens if you increase Number of cores, size of cache and speed of clock?
Improve overall computer performance
58
Increasing clock speed is known as
overclocking
59
Overclocking higher than design limits leads to...
unsynchronised operations, crashing, overheating of CPU
60
If your computer has unsynchronised operations, crashing and overheating of CPU, what might be the cause?
Overclocking
61
Unlike RAM, cache memory is located in
the CPU
62
Cache memory has ______ access times than RAM
faster
63
What has faster access times than RAM
cache memory
64
What does cache memory store?
frequently used instructions and data
65
When a CPU wants to check memory, it checks ______ first then _____
cache first, then RAM
66
Larger cache memory =
better CPU performance
67
The use of a different number of ______ can improve computer performance
cores
68
One core is made up of an ____ , ____ ___ and _______
ALU, control unit and registers
69
What's made up of an ALU, control unit and registers?
A core
70
Using more cores means less need to increase ______ ________
increase clock speed
71
What's a factor in increasing the number of cores?
CPU needs to communicate with each one which can reduce performance
72
Unicode and ASCII code are _________ _____
character sets
73
What represent letters numbers and characters found on a standard keyboard?
Unicode or ASCII
74
Whats a disadvantage of ASCII?
Not suitable for most languages around the world
75
What character set code can represent all languages of the world?
Unicode
76
Unicode is...
universal, efficient, uniform, unambiguous, supports up to 4 bytes per character
77
Each sound wave has F______, W________, A___________
frequency, wavelength, amplitude
78
Amplitude =
loudness of sound
79
Frequency, wavelength and amplitude make up _______
sound waves
80
Sound is a____________
analogue
81
Sound waves need to be __________ to be stored in a computer
sampled
82
Sampling means measuring the ____________
amplitude
83
Sound conversion is done using
ADC (analogue to digital converter)
84
Sound waves cannot be measured precisely, so amplitude values are __________
approximate
85
Sampling happens at
regular time intervals
86
bits per sample =
sampling resolution / bit depth
87
Sampling rate =
number of samples per second (in hertz, Hz)
88
How is sampling used to record a sound clip?
amplitude is determined with sampling rate, each sample encoded as series of binary digits
89
Using more bits to sample amplitude =
more accuracy of sampled sound
90
Higher sampling rate or larger resolution =
better quality sound, larger file size
91
Name 3 drawbacks of larger sampling resolution when recording sound
larger file size, takes longer to transmit/download data, requires greater processing power
92
Name 3 benefits of larger sampling resolution when recording sound
larger dynamic range, better sound quality, less sound distortion
93
What has 16-bit sampling resolution and 44.1kHz sample rate?
CDs
94
Bitmap images are made of
pixels
95
pixel =
picture element
96
Each image is made up of a _________ matrix of pixels
two dimensional
97
Pixels are represented in
binary
98
Bitmaps are stored as a series of
binary numbers
99
Black and white images only require ______ per pixel
1 bit
100
In 2 bit pixels, each pixel can be
1 of four colours
101
Number of bits used to represent each colour is called
colour depth
102
8 bit colour depth means each pixel can be _____ colours
256
103
Modern computers have ___ bit colour depth
24
104
Image resolution means
number of pixels that make up an image
105
Lower image resolution means
Less image detail
106
Pixelated means
Fewer pixels to represent the image
107
Whats the main drawback of using high resolution images?
Increase in file size
108
URLs are made up of p_______, d_____ n_____ and w__ p_____ name
protocol, domain name and web page name
109
What are protocol, domain name and web page name part of?
URLs
110
What's the first thing a user has to use to open a webpage
Browser
111
To get to a web page from a browser, you need to
type or click a link
112
What does DNS mean?
Domain Name Server
113
What does a DNS do?
Matches a URL to an IP address
114
What's an example of an IPv4 address?
192.158.29.2
115
Why do we have URLs and IP addresses
Lots of IP addresses are too hard for humans to remember
116
What's this? e.g. 192.464.55.2
IPv4 address
117
What's an IP address?
Address of a computer on a network
118
What's the address of a computer on a network?
IP address
119
What happens after the DNS has matched the URL to the IP address?
DNS sends IP address to browser
120
When the browser has the IP address, what happens next?
Requests data from the web server
121
What does a web server do?
Holds all the files and data for a web page
122
What holds all the files and data for a web page?
Web server
123
What does the web server do when it receives a request?
Sends the website data to the browser
124
What does a browser do?
Converts HTML code into text and images we can understand
125
What converts HTML code into text and images we can understand
Browsers
126
What requests data from a web server?
Browser
127
What's an example of a browser?
Chrome, Safari, Edge, Firefox
128
What sends the website data to a browser?
Web server
129
How to calculate size of image file?
multiply image resolution and colour depth
130
How to calculate size of sound file?
multiply sample rate , resolution and length of track
131
How to calculate image resolution?
Multiply height by width in pixels
132
The output X is 1 if, input A is 1 AND input B is 0, or, input A is 0 AND input B is 1
XOR
133
The output X is 1 if, neither input A or B or both, are 1
NOR
134
The output X is 1 if, input A AND input B are NOT both 1
NAND
135
The output X is 1 if, both inputs A and B are 1
AND
136
The output X is 1 if, either input A or B, or both, are 1
OR
137
The output X is 1 if, the input A is 0
NOT
138
______ ______ check the output of a logic circuit
truth tables
139
What are cookies?
A text file (stored by web browser) that contains data about a user’s browsing habits/details/preferences
140
Everytime a user visits a website, the site checks if it has set _______ on their ________ before
Everytime a user visits a website, the site checks if it has set cookies on their browser before
141
What are small files or code sent from a webserver and stored on a users computer
Cookies
142
What are the two types of cookies?
Session and persistent
143
What are session and persistent types of ?
Cookie
144
Which cookie is temporary and don't collect or store user information?
Session cookies
145
Name two facts about session cookies
Temporary, don't store/collect user info
146
Which cookies cease to exist when a browser is closed?
Session cookies
147
Session cookies _____ to ______ when a browser is closed
cease to exist
148
What are session cookies used for?
Temporary shopping baskets
149
Which cookies are used for temporary shopping baskets?
Session cookies
150
____ cookies are stored on the hard drive of a users computer
persistent cookies
151
Which cookies have an expiry date or stay until deleted?
persistent cookies
152
Which cookies remain even after the browser is closed?
persistent cookies
153
What are persistant cookies used for?
Allow website to remember usernames, passwords, emails, baskets, preferences
154
What kind of user preferences do cookies hold?
language, currency, login
155
Describe data transmission
Signals transmitted from one device to another
156
Data transmission can either be over
long distance or short distance
157
Example of short distance data transmission
computer to printer over USB cable connection
158
Example of long distance data transmission
One computer to another in a global network (i.e. internet)
159
What are the 3 factors for data transmission to happen?
Direction of transmission, method of transmission and method of synchronisation
160
What is simplex
data sent in one direction only, example is computer to printer
161
What is half-duplex?
both directions but NOT at the same time, example is walkie-talkie
162
What is full-duplex?
Both directions at the same time, example is telephone call or online gaming
163
Both directions at the same time describes what?
Full-duplex data transmission
164
Both directions NOT at the same time describes what?
Half-duplex data transmission
165
One direction only describes what?
Simplex data transmission
166
Serial data transmission is...
when data sent one bit at a time over a single wire or channel. bits are sent one after another
167
Bit sent one after another, over a single wire or channel, one bit at a time describes what?
serial data transmission
168
serial data transmission can be ....
simplex, half-duplex or full-duplex
169
Serial advantages and disadvantages
Works well over long distance, data arrives synchronised. BUT slow.
170
Example of serial data transmission
computer to printer via USB
171
Parallel data transmission is...
several bits of data (usually a byte) sent down several wires or channels at the same time. Each wire transmits one bit.
172
Parallel data transmission can be...
simplex, half-duplex or full-duplex
173
Parallel data transmission advantages and disadvantages
works well over short distances. Fast. BUT over long distances data can become skewed and arrive out of order.
174
Example of parallel data transmission
Internal circuits in a computer
175
What does PDLC mean?
Programming development life cycle
176
What is the PDLC?
Steps that are followed when developing a program (e.g. smartphone app or website)
177
What are the steps in the PDLC?
Analysis / Design / Coding / Testing
178
In the PDLC - what is analysis?
First step, the process of understanding what exactly you need as inputs to ‘build’ your product and if you have enough resources.
179
In the PDLC - what is design?
Second step refers to thinking about the technical and visual aspects of your product.
180
In the PDLC - what is coding?
Third step, programming
181
In the PDLC - what is testing?
Testing a product to make sure it works as intended
182
In programming, what is the name for the process of hiding complex details and showing only what is necessary?
abstraction
183
In programming, What is the name of the process of splitting a problem into smaller, manageable chunks?
decomposition
184
What does abstraction mean?
the process of hiding complex details and showing only what is necessary
185
What does decomposition mean?
the process of splitting a problem into smaller, manageable chunks
186
What are the 3 parts that make up analysis?
decomposition, analysis, requirements identification
187
What is the name used for the specific needs of a problem that must be identified as part of the problem analysis?
requirements
188
Requirements dictate the ______ ______ to a program.
essential inputs
189
The design process involves which representations?
structure diagrams, flowcharts, pseudocode
190
Whare are structure diagrams?
Structure diagrams are used to represent sub-systems that make up a system. Each sub-system is also split into smaller sub-systems.
191
What are flowcharts?
Flowcharts indicates the inputs needed (requirements) and the processes to be followed (logic) that lead to the output (final outcome)
192
In a flowchart, what is the flow line?
Arrow representing control passing between the connected shapes
193
In a flowchart, what is the process shape?
Represents something being performed or done
194
In a flowchart, what is a subroutine?
Subroutine call that will relate to a separate flowchart
195
In a flowchart, what is an input/output?
Input or output of something into our out of the flowchart
196
In a flowchart, what is a decision?
A decision (yes/no, true/false) that results in two lines representing different outcomes
197
In a flowchart, what is a terminator?
Start and stop of process
198
Facts about pseudocode
Resembles code but can't be understood by a computer // written for humans // easier for programmers to write and share since close to real code
199
Coding phase of PDLC is also referred to as
implementation phase, because implements design from previous stage
200
Program code is usually written in ____
IDE (integrated development environment)
201
Advantages of IDEs
Adds colour coding and indents to help organise code // helps identify errors using debugger // supports many programming languages
202
Examples of IDEs
Apache Netbeans, BlueJ and Microsoft Visual Studio Code
203
What does iterative mean?
Any action that's carried out in a loop until it produces correct outcome
204
Iterative testing is useful because...
makes sure each section of code works as intended
205
What's the difference between alpha and beta testing?
Alpha is testing it by yourself, Beta is testing on a target audience
206
____ testing is testing it by yourself, ______ is testing on a target audience
Alpha is testing it by yourself, Beta is testing on a target audience
207
Why is test data important?
Make sure the product works as intended
208
Normal data
Data within an accepted range
209
Boundary data
Values in upper and lower bounds - pair that's accepted, pair that's rejected
210
Extreme data
Data at upper and lower bounds (accepted)
211
Abnormal data
Any data that is not accepted
212
What are the 4 basic sub-systems that make up a computer system?
input / process / output / storage
213
Input / process / output / storage are...
the basic sub-systems that make up a computer system
214
Binary logical shifts mean
moving a binary number to the left or right in the table
215
A left logical shift means ________ the number by 2
multiplying
216
A right logical shift means ________ the number by 2
dividing
217
During logical shifts, empty positions are filled with
zeros
218
Left shift this binary number 1 place: 0010 << 1
100
219
Left shift this binary number 2 places: 0010 << 2
1000
220
Right shift this binary number 1 place: 1011 >>> 1
101
221
Right shift this binary number 3 places: 1011 >>> 3
1
222
Two's complement allows
representing negative integers
223
In two's complement the left-most bit is changed to a _____ value
negative
224
The left most value is changed to a negative number in _____ _________
two's complement
225
Apply two's complement to 1010
-6
226
Why does compression exist?
To reduce the size of the file
227
What's the impact of compressing files?
less bandwidth required, less storage space required, shorter transmission time
228
What are the two types of compression?
Lossless and lossy
229
_______ and _______ are the two types of compression
Lossless and lossy
230
Lossless and lossy are types of _________
compression
231
What's lossy file compression?
compression algorithm eliminates unnecessary data by permanently removing it. original file cannot be reconstructed
232
Which compression type? Compression algorithm eliminates unnecessary data by permanently removing it. original file cannot be reconstructed
Lossy
233
Examples of lossy file compression?
images - jpeg, audio - mp3, video - mp4
234
What are these file types examples of? images - jpeg, audio - mp3, video - mp4
lossy file compression
235
What's lossless file compression?
Uses compression algorithm, ALL data from original can be retrieved
236
What compression type? Uses compression algorithm, ALL data from original can be retrieved
Lossless
237
What is an example of lossless compression algorithm?
Run length encoding (RLE)
238
What's RLE?
Lossless compression algorithm
239
How do lossless compression algorithms work?
Reduce size of string of identical adjacent data, only effective if repeated patterns/words used
240
What compression algorithm, reduces size of string of identical adjacent data and is only effective if repeated patterns/words used?
Lossless compression / RLE
241
USB
Universal Serial Bus
242
How is data transmitted by USB
Uses serial data transmission / sending data to and from peripherals or devices.
243
What are advantages of USBs?
simple interface - cable only works one way so less chance of errors // relatively high speed data transfer // universal - lots of devices use USB // can be used for power // automatically detected by computer to transfer
244
What happens when you plug a USB into a computer?
Automatically detected - if it's the first time, a driver is downloaded, otherwise it works without needing to download each time
245
What are disadvantages of USBs?
Cables are limited to 5m usually // not as fast as other cables e.g. network cables
246
Why are USB cables limited to 5m usually?
More chance of errors in data transmission over long distances
247
What software is needed when a device is plugged in via USB?
Device driver
248
USB allows both _____ and ______ data transmission
full duplex and half duplex
249
Why can a computer only process binary data?
Because it consists of logic circuits/gates that can only process data in two states
250
Because computers consist of logic circuits/gates that can only process data in two states, computers can only process b______ d______
Because computers consist of logic circuits/gates that can only process data in two states, computers can only process binary data
251
In computer systems, what is an instruction?
A set of operations decoded in sequence
252
What is a set of operations decoded in sequence?
Instructions
253
In computer systems, what does each operation instruct?
ALU and CU
254
Operations are made up of ________ and ________
opcode and operand
255
Opcode
informs the CPU what operation needs to be done
256
Operand
Data which needs to be acted on OR refer to register in memory
257
What is an instruction set?
A list of all the commands that can be processed by a CPU and the commands are machine code
258
All software running on a computer contains....
a set of instructions
259
The ____ _____ ____ cycle is the sequence of steps to process each instruction
Fetch decode execute
260
Example instruction set is
X86
261
Instruction sets are written in _______ ____
machine code
262
machine code is a ____ level language
low
263
What are embedded systems?
An embedded system is used to perform a dedicated function
264
What are examples of embedded systems?
e.g. domestic appliances, cars, security systems, lighting systems or vending machines
265
What is a general purpose computer?
is used to perform many different functions
266
What is an example of a general purpose computer
e.g. a personal computer (PC) or a laptop
267
What's a microcontroller?
has a cpu, ram and rom all embedded onto one single chip to carry out a single task
268
What has a cpu, ram and rom all embedded onto a single chip to carry out a single task
microcontroller
269
What's a microprocessor?
Integrated circuit, ONLY has CPU
270
What's system on chips (SoC)?
microcontroller, ports and secondary storage
271
Advantages of embedded systems?
small, cheap, dedicated to a task, low-power, remote control, fast, reliable
272
Disadvantages of embedded systems?
difficult to upgrade or troubleshoot, interface confusing, open to hacking, encourages disposing of them
273
Embedded systems include ____, ____ _______ and ________
inputs, user interface and output (e.g. AC panel, input is buttons, user interface is display, output is air)
274
Explain embedded system of vending machine
input is buttons, user interface is display, output is actuator which pushes food
275
What is the purpose of encryption?
There's always a risk of interception when transmitting data over a public network, encryption reduces the risk
276
What does encryption mean?
Encryption alters the data into a form that is unreadable by anybody for whom the data is not intended
277
asymmetric encryption includes the use of _____ and _____ keys
public and private keys
278
Which encryption method uses public and private keys?
assymetric
279
What's plaintext?
the original data being sent
280
What's ciphertext?
Plaintext after it goes through encryption algorithm
281
In encryption, what's the original data being sent?
plaintext
282
In encryption, what's the encrypted data called?
ciphertext
283
To increase encryption security you...
increase the number of bits used in the key (e.g. 128 bits instead of 64)
284
Symmetric uses....
The same key for encrypting and decrypting
285
Which encryption method uses the same key for encrypting and decrypting?
symmetric
286
Disadvantage of symmetric encryption?
Uses same key for encrypting and decrypting
287
Scrambles data for secure transmission
encryption
288
Why is encryption effective?
If the data is stolen it's meaningless
289
How does symmetric encryption work?
Same key used for encrypting and decrypting- sender and receiver both need it
290
How does asymmetric encryption work?
Matching public and private keys are generated that are mathematically linked. Only public key sent. Both needed to decrypt.
291
What is robotics?
branch of computer science - brings together design, construction and operation of robots
292
Where can you find robots?
Factory equipment/domestic robots/drones
293
Examples of factory equipment robots are...
welding parts together, spray painting, fitting windscreens to cards, cutting metal parts, bottling and labelling objects, warehouse operations
294
Examples of domestic robots are...
autonomous floor sweepers, autonomous lawn mowers, ironing robots, pool clearning, automatic window cleaners, entertainment (robot friends)
295
Examples of drones are...
UAVs, reconnaisance (photos), parcel delivery
296
What are the 3 characteristics of a robot?
Sense surroundings, degree of movement, programmable
297
Explain how robots sense surroundings
sensors allow robot to recognise immediate environment and give it ability to determine things like shape, size, weight of objects
298
What are examples of sensors robots use?
light, pressure, temperature, acoustic
299
Explain movement in robots
make use of wheels, cogs, pistons to carry out functions such as twisting, turning, moving, gripping or lifting // they are mechanical structures made up of many parts // contain electrical components // can make use of effectors
300
What are examples of end effectors in robots?
welding, spraying, cutting, lifting
301
What determines action to be taken in a robot?
controller
302
Controllers in robots allow...
action to be taken to perform a task. Controllers rely on sensors/cameras for data and are programmable
303
In robots, what rely on sensors/cameras for data and are programmable?
controllers
304
What are examples of software robots (bots?)
webcrawlers, search engines, chatbots
305
What are the two types of physical robots?
independent and dependent
306
Explain independent (physical) robots
have no direct human control, autonomous, can replace the human activity totally, no human interaction required for full function
307
What's an example of a independent robot?
robot vacuum cleaner
308
Explain dependent (physical) robots
has a human interfacing with the robot directly, can supplement, rather than replace human activity
309
What's an example of a dependent robot?
car assembly plant where humans and robots work together
310
What are types of AI?
image recognition, speech recognition, natural language, computer games, diagnostic systems
311
What is image recognition?
identify objects or people in an image
312
What is speech recognition?
Identify words spoken by humans and store them
313
What is natural language?
To receive a command or instruction that is not in a set format and perform the required task (e.g. Siri question)
314
What use is AI in computer games?
to move elements or characters independently based on the environment
315
What is a diagnosis system in AI?
e.g. to diagnose medical problems
316
What are the features of AI programs?
collect data, programmed rules, ability to reason, ability to learn and adapt
317
What is collecting data in AI?
programs need data input - data might come from users or from sensors
318
What are programmed rules in AI?
Programs use rules to make decisions
319
What is the ability to reason in AI?
An area of logic. In logic you have rules and can develop facts
320
What is the ability to adapt and learn in AI?
Not all AI does this, its known as machine learning and requires training a program
321
What is an expert system?
An attempt to emulate the expertise of a human, e.g. doctor or engineer
322
How do expert systems work?
System asks questions to determine the solution, depending on answers given it will ask different questions
323
What's an example of an online expert system?
Online chat bot to help you with a problem
324
What are the features of expert systems?
Knowledge base, rule base, inference engine, user interface
325
In expert systems, what's a knowledge base?
list of facts
326
In expert systems, what's a rule base?
Links the facts
327
In expert systems, what's an inference engine?
Decides which question to ask next or which answer it gives
328
In expert systems, what's a user interface?
Outputs questions and other statements to the user and allows them to enter data
329
What is machine learning?
A system that has the ability to learn and adapt, and change their own rules and logic. It involves training.
330
What is supervised machine learning?
Supervised means that user is telling the program what its data means.
331
What is unsupervised machine learning?
Unsupervised means that data is input, and then the program learns from the data.
332
What's system software
Services a computer requires
333
What are services a computer requires called?
system software
334
What are services that a user requires called?
Application software
335
Examples of system software
operating system, utility programs, device drivers
336
Examples of application software
spreadsheets, word processors, instagram app, browsers
337
What are spreadsheets, word processors, youtube app examples of?
application software
338
What are operating systems, utility programs, device drivers examples of?
system software
339
general features of system software
control and manage operation of hardware, HCI, allows hardware and software to run without problems, platform on which other sofware can run
340
general features of application software
perform variety of tasks, applications, apps / users can perform specific tasks / can be single programs / users can execute as required
341
Features of operating systems
run in background, allows input/output operations, users can interact with hardware, handles errors, loads and runs programs, manages security
342
features of utility programs
manage and maintain computer resources, designed to carry out specific task, e.g. anti-virus, backups, disk repair
343
features of device drivers
enables hardware to communicate with operating system
344
What is firmware?
program that provides low-level control for devices
345
BIOS
Basic Input Output System (Firmware)
346
Firmware is run on h_______
hardware
347
Applications are run on the o________ s______
operating system
348
Operating system is run on f________
firmware
349
Bootloader is another name for f
firmware
350
Bootloading also known as b_________
booting
351
What is an IDE?
Integrated Development Environment is use to help write computer programs
352
What do programmers use to help write programs?
IDEs
353
What are examples of IDEs
Pycharm (for Python), Visual Studio (for Visual Basic)
354
What are Pycharm (for Python), Visual Studio (for Visual Basic) examples of?
IDEs
355
What are the features of IDEs?
code editor, translator, runtime environment with debugger, error diagnostics, autocomplete, autocorrect, pretty printing
356
What are these features of...code editor, translator, runtime environment with debugger, error diagnostics, autocomplete, autocorrect, pretty printing?
IDEs
357
Describe an IDE code editor
Allows program to be written without using a separate text editor, which makes programming faster
358
Describe a runtime environment with a debugger in an IDE
Allows programmer to run a program a line at a time and check for errors.
359
Describe error diagnostics in an IDE
Finds possible errors as the code is being typed
360
Describe pretty printing in an IDE
Colour codes the words in the program and lays it out in a meaningful way
361
What colour codes words in a program and lays it out in a meaningful way?
Pretty printing
362
What is an interrupt?
A signal to the processor to tell it something needs it attention. Can be software or hardware based
363
What is a signal to the processor to tell it something needs it attention. Can be software or hardware based.
Interrupt
364
Examples of software interrupts
divide by zero, two processes attempting to access the same memory location, program request for input
365
What are divide by zero, two processes attempting to access the same memory location, program request for input, examples of?
Software interrupts
366
Examples of hardware interrupts
Error from hardware e.g. printer out of paper, new hardware device conected
367
What are error from hardware e.g. printer out of paper, new hardware device conected , examples of?
Hardware interrupts
368
How does a computer decide the priority of an interrupt to service the interruption?
Managed by an interrupt handler
369
What does an interrupt handler do?
Decides the priority of interrupts and what to service first
370
What happens when an interrupt is sent to the processor?
Processor store the current process and fetches the interrupt // Next, checks the source of the interrupt // Calls the relevant Interrupt service routine to handle it // When finished the stored process is returned to memory
371
The internet can be described as....
an infrastructure
372
An infrastructure is a way of describing
the internet
373
An infrastructure means all...
parts are connected in a huge network
374
All parts connected in a huge network is called an
infrastructure
375
What can you do on the internet?
send/receive emails, chatting (video, text, audio), share files
376
What makes use of transmission protocols (TP) and internet protocols (IP)
The internet
377
What is a world wide collection of internet connected networks and devices?
The internet
378
The internet uses transmission _________ and internet ___________
protocols
379
URL
uniform resource locator
380
URLs are made up of 3 things....
protocol, domain, webpage
381
Protocol, domain and webpage are part of....
URLs
382
Every website and webpage has a
URL
383
What's a text address used to access websites?
URL
384
HTTP means
Hyper text transfer protocol
385
www.google.com is made up of...
domain host (www), domain name (Google ), domain type (.com)
386
URLs consist of
protocol://website address /path/filename
387
In a URL the protocol is...
http or https
388
In a URL the domain name is broken into 3 pieces...
domain host (www), domain name (name e.g. Google, Youtube), domain type (e.g. .com .gov. kr)
389
HTTP is secure if
is HTTPS
390
URLs are t_____ addresses to access websites
URLs are text addresses to access websites
391
HTTP means H_____T_____ T_____ P_______
HyperText Transfer Protocol
392
Another sign that a website is secure, other than HTTPS protocol is...
Padlock in the address bar
393
A padlock in the address bar next to HTTPS means
Site is secure
394
Web browsers are...
software that allows users to access and display web pages on their devices
395
Browsers translate ______ to images, video, text and audio
HTML
396
What do browsers translate HTML into?
images, video, text and audio
397
What is software that allows users to access and display web pages on their devices?
Web browsers
398
Most browsers have what features?
Home page, favourites/bookmarks, history, tabs, use cookies, use links, have an address bar
399
What are these features of - Home page, favourites/bookmarks, history, tabs, use cookies, use links, have an address bar
Web browsers
400
Name 5 browsers
Chrome, Edge, Safari, Firefox, Opera
401
What are Chrome, edge, safari, firefox, opera examples of?
Browsers
402
The world wide web the name for
all websites and webpages
403
All websites and webpages are known as
the world wide web (www)
404
Websites are a collection of
webpages
405
A collection of webpages is called
a website
406
WWW uses what protocol?
HTTP(S)
407
Web resources are accessed using
web browsers
408
HTTP(S) protocol is written using
HTML
409
What is the part of the internet that's only accessible through web browsers?
World Wide Web
410
What uses the internet to access information from web servers?
World Wide web
411
___ resources are accessed by ____ browsers
web / web
412
Payments can be sent digitally over the internet using...
Paypal, Apple Pay, Kakaopay and more
413
Digital payments over the internet are secure because they are
Encrypted
414
The central authority for currencies are
banks
415
Banks are the ________ _________ for currencies
central authority
416
An example of a central bank is....
Bank of England, Bank of Korea
417
Examples of cryptocurrencies are
bitcoin, dogecoin, ethereum, cardano
418
bitcoin, dogecoin, ethereum, cardano are examples of
cryptocurrencies
419
Bank of England and Bank of Korea are examples of
central banks
420
Cryptocurrency has no ________ _________
central authority
421
What has no central authority for payments?
cryptocurrencies
422
No central authority is also called
Decentralised
423
Decentralised
means no central authority
424
Cryptocurrency payments over the internet are secure because
they are encrypted
425
Payments are made for cryptocurrencies using...
blockchain
426
Blockchain is how _________ payments are made
Cryptocurrency
427
A blockchain is like a
digital ledger or list of all records of payment
428
Blockchains record...
All payments with time and date stamps
429
Once added to a blockchain, records....
cannot be changed
430
Blockchains are accessible by...
every connected computer
431
USB
Universal Serial Bus
432
How is data transmitted by USB
Uses serial data transmission / sending data to and from peripherals or devices.
433
What are advantages of USBs?
simple interface - cable only works one way so less chance of errors // relatively high speed data transfer // universal - lots of devices use USB // can be used for power // automatically detected by computer to transfer
434
What happens when you plug a USB into a computer?
Automatically detected - if it's the first time, a driver is downloaded, otherwise it works without needing to download each time
435
What are disadvantages of USBs?
Cables are limited to 5m usually // not as fast as other cables e.g. network cables
436
Why are USB cables limited to 5m usually?
More chance of errors in data transmission over long distances
437
What software is needed when a device is plugged in via USB?
Device driver
438
USB allows both _____ and ______ data transmission
full duplex and half duplex
439
Why keep data safe?
It has either personal or business value
440
Examples of personal information/data?
credit card number, bank account, date of birth, passport number, passwords
441
Data can be...
corrupted, deleted, or intercepted - maliciously or accidentally
442
What is a brute force attack?
A hacker tries to crack a password using all combinations of characters
443
What hacking is when a hacker tries all combinations of characters?
brute force attack
444
What is a wordlist?
A very large text file containing common words for passwords
445
Name facts about brute force attacks
No sophistication, time consuming, often uses wordlists
446
What is data interception?
Stealing data by tapping into wired or wireless communcation links
447
What is stealing data by tapping into wired or wireless communication links?
Data interception
448
Wired data interception uses a
packet sniffer
449
What do packet sniffers do?
Look at packets going over a network
450
Wireless data interception is also called
wardriving/ access point mapping
451
What makes wireless data interception harder to do?
If data is encrypted using Wireless Equivalency Privacy (WEP)
452
DoS
Denial of Service
453
DDoS
Distributed Denial of Service
454
What is the purpose of a DoS or DDoS?
Attempt at preventing users from accessing part of a network
455
DoS or DDoS facts
Usually an internet server, usually temporary, very damaging and large breach of security, can be individual or group target
456
What is a cyber attack that is..usually an internet server, usually temporary, very damaging and large breach of security, can be individual or group target
DoS or DDoS
457
What's the difference between a DoS and DDoS?
DDoS comes from many different computers all around the world
458
How does a DoS or DDoS work?
Floods a network with spam traffic and web servers can only handle so many requests, so they become overloaded and can't answer legitimate requests
459
How can you prevent DoS or DDoS?
Use up to date malware blockers / use firewalls to restrict traffic / use filters to block spam
460
What are the signs of a DoS or DDoS?
V slow internet on network / can't access some websites / large amounts of spam
461
What is meant by phishing?
Creator sends out legitimate looking email; as soon as recipient clicks on a link in the email/attachment, the user is sent to a fake website
462
What are the effects of phishing?
Loss of personal data such as bank account numbers. Can also lead to identity theft.
463
How to prevent phishing?
Be aware and cautious when opening emails or attachments. Use anti-phishing software. Look for HTTPS
464
What's spear phishing?
Attacks a specific individual to gain access to sensitive information
465
What's the difference between phishing and spear phishing?
Spear phishing attacks one person, phishing attacks many
466
What's the aim of phishing?
Steal personal data like credit cards and bank information
467
What is meant by pharming?
vicitim clicks a link and malicious code installed on their computer which redirects to fake website to steal personal information
468
How do you prevent pharming?
Install anti-malware, don't click suspicious links
469
What's a virus?
Replicates itself, corrupts data
470
What's a worm?
Replicates itself, finds weaknesses in networks and slows them down
471
What's spyware?
Records actions on a computer
472
What's an example of spyware?
Keylogger
473
What's a trojan horse?
Used to disguise other malware
474
What's adware?
Designed to create advert banners and popups when online
475
What's ransomware?
Encrypts data so you can't access it, creators demand ransom to give it back
476
What replicates itself, corrupts data?
Viruses
477
What replicates itself, finds weaknesses in networks and slows them down?
Worms
478
What records actions on a computer?
Spyware
479
What's a keylogger?
Example of spyware
480
What's used to disguise other malware?
Trojan horse
481
What's designed to create advert banners and popups when online?
Adware
482
What encrypts data so you can't access it, creators demand ransom to give it back?
Ransomware
483
Name three protections against malware
Anti-malware, firewalls, backups
484
What 3 things does anti-malware do?
Scans, quarantines and deletes any malware found
485
What's a firewall?
Helps prevent malware - looks at data coming in and out of a computer
486
What scans, quarantines and deletes any malware found?
Anti-malware
487
What helps prevent malware - looks at data coming in and out of a computer?
Firewalls
488
What looks for spyware?
Anti-spyware
489
Social engineering is...
When a perpetrator will try and manipulate and deceieve someone into providing them with personal or confidential data
490
What's it called when a perpetrator will try and manipulate and deceieve someone into providing them with personal or confidential data?
Social engineering
491
What's the aim of social engineering?
To get data to commit criminal activity, such as stealing money, hacking into a computer network, and identity theft or fraud
492
How can you prevent social engineering?
Access levels to data and staff training of how social engineering works
493
What is a word list
a text file containing a collection of words used in a brute force attack
494
What is packet sniffing?
a method used by a cybercriminal to examine data packets being sent over a network and to findthe contents of a data packet, which are sent back to the cybercriminal
495
What's wardriving?
using a laptop, antenna, GPS device and software to intercept Wi-Fi signals and illegally obtain data;sometimes called Access Point Mapping
496
What's spam?
unsolicited emails sent to a user’s mailbox
497
What are access levels?
different levels of access in a computer system allowing access depending on the users security level
498
What's anti-spyware?
software that detects and removes spyware programs installed on a system; the software is based on typical spyware rules or known file structures
499
What's a patch?
An update for software that improves its and/or removes bugs
500
What's a SSL certificate?
A form of digital certificate that authenticates a website, and any data transmission between the browser and website is secure
