computer_science_flashcards

Question 1

Limitation of ASCII

Answer 1

Not enough bits to represent all characters.

Question 2

Characteristics of lossy compression

Answer 2

Data is permanently removed so the original file cannot be reconstructed.

Question 3

Why are there no collisions on a ring network?

Answer 3

Data packets only travel in a single direction from node to node, so there are no packet collisions.

Question 4

TCP/IP layers from highest to lowest

Answer 4

Application, Transport, Network, Data Link

Question 5

What does the Application layer handle?

Answer 5

Selects & uses the correct protocol to transmit data & interacts with the user.

Question 6

Drawbacks of cellular phone networks

Answer 6

Some areas not covered by infrastructure & inconsistent connection due to interference.

Question 7

Describe one function of cache

Answer 7

Holds data ready for use so that it speeds up the processing.

Question 8

How can an RFID be used?

Answer 8

A hand-held receiver could be used to detect the location of a lost object.

Question 9

How does technology make us a more inclusive society?

Answer 9

Provides access to services such as education & health for those with constraints.

Question 10

What does a round rectangle represent in flowcharts?

Answer 10

Start/Stop

Question 11

What does a parallelogram represent in flowcharts?

Answer 11

Input/Output

Question 12

What does a rectangle represent in flowcharts?

Answer 12

Process

Question 13

What does a rhombus represent in flowcharts?

Answer 13

Decision

Question 14

Function of a compiler

Answer 14

Translates high-level programming languages & generates single executable file.

Question 15

Function of an interpreter

Answer 15

An error in the source code is highlighted as soon as it is encountered during execution, and translates high-level programming languages.

Question 16

Function of an assembler

Answer 16

Translates low-level programming languages. One line of source code is translated to one line of machine code.

Question 17

Benefit of hacking a network

Answer 17

Security vulnerabilities are exposed to an ethical hacker.

Question 18

Describe how data is stored on optical media

Answer 18

A laser beam is used to burn pits & lands on the disc which represent 0 and 1.

Question 19

Disc-formatting program software type

Answer 19

System software

Question 20

Cloud storage user responsibility

Answer 20

Choosing strong authentication credentials & not sharing these.

Question 21

Cloud storage provider responsibility

Answer 21

Encryption, backup & restore procedures

Question 22

DNS Input

Answer 22

Uniform resource locator into browser

Question 23

DNS Output

Answer 23

IPv4 address of searched website

Question 24

Layer of devices from user device to internet

Answer 24

Device, Switch, Router, Modem, ISP, Internet

Question 25

IMAP Explanation

Answer 25

Changes are synced with the mail server in real-time

Question 26

What happens during too large binary addition?

Answer 26

An overflow error occurs which can cause the program to crash or produce incorrect results.

Question 27

Benefits of embedded systems

Answer 27

Low power consumption, limited memory, can be chosen to fit just one specific task.

Question 28

Reasons for networks

Answer 28

Centralised backup & saves money on licenses

Question 29

Advantages of wired networks

Answer 29

More secure, more bits per second, connection does not get stopped by walls & furniture.

Question 30

Disadvantages of wired networks

Answer 30

Less portable, installation more complex, some digital devices cannot use wired

Question 31

Definition of internet

Answer 31

A global network of networks

Question 32

Definition of World Wide Web

Answer 32

Collection of web pages accessed using the internet

Question 33

Why was Unicode developed?

Answer 33

Standard ASCII can’t represent all major characters & symbols, but Unicode can represent a very large number of characters

Question 34

How does increasing cache improve CPU performance?

Answer 34

It speeds up processing because the cache is a faster type of memory.

Question 35

What is hertz?

Answer 35

Samples per second

Question 36

Code reviews benefits

Answer 36

Remove code vulnerabilities in programming languages & eliminate bad programming practices

Question 37

4 Types of legal protection for intellectual property

Answer 37

Trademark, Licensing, Copyright, Patent

Question 38

Pixel definition

Answer 38

The smallest single dot in an image

Question 39

Task carried out by network layer

Answer 39

Adds the sender's IP adress and destination IP address & routes packets

Question 40

Why is both software & hardware needed?

Answer 40

Software is the set of instructions that controls the hardware

Question 41

Why is an SSD better than other storage devices?

Answer 41

It is lighter, generates less heat & has faster access speed.

Question 42

Why are simulations used?

Answer 42

To predict outcomes & to speed up or slow down simulations

Question 43

Why do simulators require powerful processors?

Answer 43

Simulations may collect large amounts of data & may involve a large number of calculations

Question 44

Describe the stored program concept

Answer 44

Instructions & data are stored in memory & fetched, decoded & executed.

Question 45

Difference between DNA & traditional computing

Answer 45

DNA uses chemical reactions rather than electrical properties

Question 46

How to prevent shoulder surfing?

Answer 46

Shield your screen when entering sensitive information to stop people seeing sensitive information.

Question 47

Radio frequency used by smartphones

Answer 47

2.4 GHz

Question 48

Benefit of higher frequency band

Answer 48

Higher frequency gives greater bandwidth

Question 49

Benefit of 5G rather than 3G

Answer 49

Gives faster response to communications allowing user to download data in shorter time.

Question 50

How does program counter keep track of next instruction to be fetched?

Answer 50

Stores a memory address for the next instruction. Memory address incremented during fetch process.

Question 51

Benefit of low-level programming language

Answer 51

Faster translation & execution

Question 52

Program instruction definition

Answer 52

A task that is carried out by the CPU

Question 53

Memory address definition

Answer 53

An identification of a location in memory

Question 54

Benefit of higher clock speed

Answer 54

More instructions can be carried out per second & processes run faster

Question 55

Purpose of assembler

Answer 55

To translate assembly language into object code

Question 56

Reason for low-level programming language

Answer 56

When writing code for a particular hardware

Question 57

Unicode over ASCII

Answer 57

Unicode can represent any language whereas ASCII can only represent English characters

Question 58

X-axis on a digital sound wave graph

Answer 58

Time OR Sample interval

Question 59

Disadvantage of lossless on cloud storage

Answer 59

Larger file size so takes up more storage space

Question 60

Benefit of cloud storage

Answer 60

Files can be uploaded & downloaded anywhere & anytime so long as there is internet connection

Question 61

Security issue with cloud storage

Answer 61

Files could be intercepted during upload/download

Question 62

URL component HTTP

Answer 62

Protocol

Question 63

Why is mesh essential for internet?

Answer 63

Enables it to span a huge geographical area because additional nodes can be added to expand coverage

Question 64

How does SSD store data?

Answer 64

Flash memory chips are used. Chips have floating gate transistors. Electron pools hold an electric charge which remains when no power.

Question 65

Benefit of PAN over free Wi-Fi?

Answer 65

Faster connection speed because fewer devices are sharing the bandwidth

Question 66

Audit trail definition

Answer 66

A record of activities that have taken place on a computer system

Question 67

Audit trail purpose

Answer 67

To identify suspicious activity