Computers

Question 1

What is the stored program concept?

Answer 1

Where there is main memory and a central processing unit interconnected by buses with some form of secondary storage for long-term storage

Question 2

What is the role of the clock?

Answer 2

Synchronises the actions of the CPU

Question 3

What is the role of the control unit?

Answer 3

Fetches program instructions from main memory one at a time, decodes them and directs the operations of the other parts of the system to execute them

Question 4

What is the role of the arithmetic logic unit?

Answer 4

Performs arithmetic and logic operations on data

Question 5

What is the role of registers?

Answer 5

Direct-access storage for instructions, intermediate results and data within the CPU.

Question 6

What is an embedded system?

Answer 6

A small computer that performs a dedicated task within a bigger system

Question 7

What are some features of an embedded system?

Answer 7

1. Single purpose
2. Low power consumption
3. Minimal or no user interface
4. Small physical size
5. Low maintenance

Question 8

What is an operating system?

Answer 8

A program that acts as an interface between the hardware and software in a computer system

Question 9

How does an OS manage files?

Answer 9

Files are stored in a hierarchal tree structure with the root directory at the top, branching off into directories, sub-directories and files

Question 10

What is a code review?

Answer 10

Where another programmer or specialised software checks the code to find any vulnerabilities in the code. It may also suggest way to fix them

Question 11

What is an audit trail?

Answer 11

It keeps track of who made what changes and when during the development changes. Should a problem be discovered, the code can be rolled back to a version before the flaw was introduced

Question 12

What is a low-level language?

Answer 12

Machine code and assembly language that work directly with a computer’s hardware

Question 13

What are the advantages and disadvantages of low-level languages?

Answer 13

ADV:
1. Interact directly with the hardware, enabling memory to be used efficiently
DIS:
1. Are difficult and time consuming to use
2. Have few tools to help with maintenance and debugging
3. Are machine-specific

Question 14

What is a high-level language?

Answer 14

A language much closer to human language - Java and Python

Question 15

What are the advantages and disadvantages of high-level languages?

Answer 15

ADV:
1. Programmer friendly
2. Have tools that make maintenance and debugging easier
3. Are machine-independent
DIS:
1. Are generally less memory efficient

Question 16

What is a compiler?

Answer 16

A compiler translates the source code into a stand alone machine code that can then be executed

Question 17

What are the properties of compilers?

Answer 17

1. The translation is done once and as a separate process
2. The program that is run is already translated into machine code so it can be execute more rapidly
3. It protects the software from competitors who would otherwise be able to see the source code
4. If it encounters any errors, it carries on and reports them at the end
5. You cannot change the program without going back to the original source code

Question 18

What is an interpreter?

Answer 18

An interpreter translates the high-level code line by line into machine code.

Question 19

What are the properties of interpreters?

Answer 19

1. When an error is found, the interpreter stops, and reports it
2. The code is not platform-specific and can be run on different operating systems
3. The program can be easily edited as it always exists as source code
4. Every line has to be translated each time it is executed, and therefore slower to run

Question 20

What is an assembler?

Answer 20

An assembler translates the assembly language into machine-code instructions