Systems

Question 1

Two main types of translators

Answer 1

Compiler

Interpreter

Question 2

Compiler

Answer 2

A compiler translates a complete high level program by converting every instruction into machine code before it executes the program.

Question 3

Interpreters

Answer 3

An interpreter translates a high level language program one line at a time then performs the high level command. This is repeated until the whole program has been interpreted.

Question 4

Compiler Advantages

Answer 4

• Only translate once
• Immediately available for use
• Runs faster than interpreted programs
• Can be loaded and executed on other computers which do not have the translator programs

Question 5

Compiler Disadvantages

Answer 5

• Program errors are only detected when the program is compiled
• Development of programs is awkward as the whole program has to be compiled before it can be run

Question 6

Interpreter Advantages

Answer 6

It error checks each line of a program as it is written which is useful for people learning to program

Question 7

Interpreter Disadvantages

Answer 7

• The program has to be translated every time it is executed

- Runs slower than compiled programs

Question 8

How many bits are in a byte?

Answer 8

8

Question 9

01100110

Answer 9

102

Question 10

67

Answer 10

01000011

Question 11

What is the Mantissa of 0.75843 x 10³

Answer 11

75843

Question 12

What is the exponent of 0.75843 x 10³

Answer 12

3

Question 13

How are real numbers stored

Answer 13

Floating point representation - Mantissa and Exponent

Question 14

How is text stored in the computer?

Answer 14

ASCII
8 bits
Each character has its own 8 bit number

Question 15

What does ASCII stand for?

Answer 15

American Standard Code for Information Interchange

Question 16

Vector Graphic Shapes

Answer 16

• Rectangle
• Ellipse
• Line
• Polygon

Question 17

Vector Graphics Attributes

Answer 17

x/y co-ordinates
Fill colour
Line colour

Question 18

Vector Graphics Advantages

Answer 18

• Do not lose quality when scaled
• Require less storage space
• Objects are easily moved/manipulated
• Resolution independent

Question 19

Bitmap Graphics Advantages

Answer 19

• Can be manipulated at pixel level
• Can create a wide array of graphic effects
• Can represent photo-realistic images

Question 20

Bitmap Graphics Disadvantages

Answer 20

• Requires large storage space

- Image becomes jagged when scaled

Question 21

The two types of main memory

Answer 21

RAM (random access memory)

ROM (read only memory)

Question 22

RAM

Answer 22

Random Access Memory
The computers short term memory
It’s volatile - when power is lost, contents of RAM are also lost

Question 23

ROM

Answer 23

Read only memory
Always retain it’s memory even when power is lost
Used by mobile phones to store operating systems

Question 24

Backing Storage

Answer 24

Used to store permanent copies of our files

Examples: Hard Disk Drives, USB Flash Drives, Magnetic Tapes, CD/DVD

Question 25

Input Devices

Answer 25

Enters data into the computer. eg. keyboard and mouse

Question 26

Output Devices

Answer 26

Generate output from the computer. eg. printer

Question 27

What are the different parts of the processor?

Answer 27

Control Unit Arithmetic and Logic Unit (ALU) Registers

Question 28

Control Unit

Answer 28

This controls the order of execution and the timing of instructions

Question 29

Arithmetic and Logic Unit (ALU)

Answer 29

This performs the calculations for the processor . It also carries out the logical decisions.

Question 30

Registers

Answer 30

These are temporary stores of information, at best they will store a few bytes of information.

Question 31

Data Bus

Answer 31

The data bus is used to carry data to and from the CPU and Memory It will hold a binary word

Question 32

Address Bus

Answer 32

This carries the address of the memory that is being used

Question 33

What is a bus?

Answer 33

A bus is a collection of wires which can carry data

Question 34

Name 3 Security Risks

Answer 34

``` Viruses Worms Trojans DOS (Denial of Service) Attacks Spyware Keylogging Phishing Identity Theft Online Fraud ```

Question 35

Name 3 Security Precautions

Answer 35

``` Anti-virus software Passwords/encryptions Biometrics Security Protocols and Firewalls Use of Security Suites ```

Question 36

Firewall

Answer 36

Used to stop hackers and viruses from accessing a computer

Question 37

Name 2 uses of firewalls

Answer 37

Check that incoming packets meet specific rules before beings allowed in. Set rules about which stations on a network can send or receive packets. Rules are created that take account of the following: - Sender IP Address - Receiver IP address - port numbers - protocols

Question 38

Carbon Footprint DONT NEED TO KNOW THIS SULA

Answer 38

The measurement of greenhouse gasses produced from the manufacture, and the use and disposal of computing equipment

Question 39

Negative effects of using computers

Answer 39

Raw materials and energy used to manufacture computing equipment, including smartphones Energy used to power laptops, desktops, mainframes and servers Internet use is increasing all the time. As it increases so does power consumption

Question 40

Positive effects of using computers

Answer 40

Most manufacturers are now producing devices with low-energy consumption Many workers now telecommute Save paper by using digital instead of hardcopies

Question 41

3 ways to reduce energy use

Answer 41

Change settings of your monitor Change the power settings - energy saver Set computer to automatically power down at the end of the day Leave computer on stand by

Question 42

What should you do with the hard disk if the computer is to be scrapped and why?

Answer 42

Shred it to prevent identity theft

Question 43

Why is data encrypted before sending?

Answer 43

Prevents unauthorised access | Scrambled to make data unreadable

Question 44

How is a bit-mapped graphic represented in a computer system’s memory

Answer 44

each pixel is stored as a binary value