Computer Systems

Question 1

What is application software

Answer 1

Programs set to complete a specific task - Word processor, web browser etc.

Question 2

What is system software?

Answer 2

Software which operates, maintains and controls the computer and its components.

Question 3

Give examples of system software.

Answer 3

• Operating system
• Utility programs
• Library programs
• Translators

Question 4

What is the operating system?

Answer 4

System allowing users to control the computer with easy - provides virtual machine abstracting complexity of computer from user.

Manages and controls access to computers resources - memory management, processor scheduling, interrupts etc.

Question 5

What are utility programs? Give some examples.

Answer 5

Programs which are used to aid computer system.

• Data backups
• Defragmenting hard drives
• Compression
• Encryption

Question 6

What are library programs?

Answer 6

LIbraries - contain useful functions frequently used by a program.
Simplify developing programs - first import it.

Question 7

What are translators? Name the 3.

Answer 7

Software to translate between different types of language
- Compilers
- Assemblers
- Interpreters.

Question 8

What is machine code?

Answer 8

Language which uses only binary digits to represent instructions.

Question 9

Name the positives and negatives of machine code.

Answer 9

Pros:
- Very powerful
- Programmers are not constrained
- Doesn’t require translation before execution
- Excellent for embedded systems.

Cons:
- Code can be very long
- Extremely difficult for humans to understand.
- Prone to errors
- Difficult to debug.
- Platform specific

Question 10

What is Assembly language?

Answer 10

Use of mnemonics to simplify the process of writing computer programs. Each instruction has 1to1 correlation to machine code instruction.

Question 11

Name some positives and negatives of assembly language.

Answer 11

Pros:
- Compact
- Easier than machine code.
- Less error prone

Cons:
- Requires an assembler to convert to machine code
- Uses mnemonics - have to remember what they do to code.
- platform specific.

Question 12

What are high-level languages?

Answer 12

Coding language which uses english instructions and mathematical symbols in the code. Use built-in functions to save time while programming.

Question 13

State some positives and negatives of high-level languages.

Answer 13

Pros:
- easier to code and understand for humans
- Easier to debug - often comes with debugging software.
- Quickest to code.
- Not platform specific

Cons:
- Requires compiler or interpreter before being executed - Takes time.

Question 14

What is an assembler?

Answer 14

Translates assembly language into machine code. Quick and easy - assembly is 1to1 to machine code.

Question 15

What is a Compiler

Answer 15

Translates high-level code into machine code. Takes time, compiles all code at once then runs program. Once translated, runs program without any other software.

Question 16

What is an interpreter?

Answer 16

Translates high-level code into machine code line-by-line. Error checking occurs during run-time. Both source code and interpreter has to be present - Source code not well protected.

Question 17

What is an intermediate language?

Answer 17

Code which has been translated from high-level code which will then be converted into machine code (bytecode).

Question 18

What is the use for intermediate languages?

Answer 18

Allows for platform independence - Intermediate language run in virtual machine to execute on different processors.