1.2.2 Applications Software

Question 1

What is the difference between applications and system software?

Answer 1

Applications software is utilised directly by the end-user whereas systems software ensures the high performance of the computer.

Question 2

Give 3 examples of utilities:

Answer 2

Three from:

• Compression
• Disk defragmentation
• Antivirus
• Automatic backup
• Automatic updating

Question 3

Gives 1 advantage of using closed source code:

Answer 3

Any from:

• Thorough, regular and well-tested updates
• Expert support and user manuals from company
• High levels of security as it is developed in a professional controlled environment

Question 4

State 2 features of open source code:

Answer 4

Any 2 from:

• Does not require a license to be used
• Distributed with the source code
• Can be modified and sold on

Question 5

Give 2 advantages of using compiled code over interpreted code:

Answer 5

• Faster to execute

- Does not require a compiler to run

Question 6

Give 2 advantages of using interpreted code over compiled code:

Answer 6

Two from:

• Is platform independent
• Runs instantly without tile waiting for compilation
• Useful for debugging

Question 7

What is assembly language?

Answer 7

A low-level language that almost has a 1-to-1 relationship with machine code. It is platform specific.

Question 8

What are the stages of compilation?

Answer 8

Lexical analysis
Syntax analysis
Code generation
Optimisation

Question 9

What happens during syntax analysis?

Answer 9

• Tokens are compared to the rules of programming language
• Syntax errors are identified
• Symbol table updated with more details
• Semantic analysis (finding logic errors)

Question 10

What are the similarities and differences between static and dynamic linkers?

Answer 10

Similarities: Both link external modules and libraries to main program

Static: Library code copied into the file. File size increased

Dynamic: Addresses libraries included within file. External updates automatically feed through to main program

Question 11

Give 3 advantages of using libraries:

Answer 11

Three from:

• Error free
• Saves time
• Re-usable
• No need to “reinvent the wheel”
• Designed by experts

Question 12

Describe the function of a loader:

Answer 12

Provided by the OS, a loader retrieves the library or subroutine from the given memory location.

Question 13

What is the purpose of optimisation stage of compilation?

Answer 13

• Reduce execution time
• Reduce inefficient sections of code
• Remove redundant code