1.2.2. Applications Software

Question 1

What is the difference between applications and systems software?

Answer 1

applications software is utilised directly by the end-user where as systems software is low-level software that is responsible for running the computer system smoothly

Question 2

What are 3 examples of utilities?

Answer 2

1. file compression
2. disk defragmentation
3. antivirus
4. Auto updates
5. Back ups

Question 3

What are 3 advantages of using closed source code?

Answer 3

1. thorough, regular and well-tested updates
2. expert support and user manuals from company
3. high levels of security as it is developed in a professional, controlled environment

Question 4

What are 3 features of open source code?

Answer 4

1. does not require a license to be used
2. can be modified and sold
3. distributed with the source code

Question 5

What are 2 advantages of using compiled code over interpreted code?

Answer 5

1. faster to execute
2. does not require a compiler to run

Question 6

What are 3 advantages of using interpreted code over compiled code?

Answer 6

1. it is platform independent
2. runs instantly without having to wait for compilation
3. useful for debugging

Question 7

What is an assembly language? (2 things)

Answer 7

1.a low-level language, that almost has a one-to-one relationship with machine code
2.it is platform specific

Question 8

What are the 4 stages of compilation in order?

Answer 8

1. lexical analysis
2. syntax analysis
3. code generation
4. optimisation

Question 9

What 4 things happen during syntax analysis?

Answer 9

1. tokens are compared to the rules of the programming language
2. syntax errors are identified and an abstract syntax tree is produced
3. symbol table is updated with more details
4. semantic field analysis (finding logic errors)

Question 10

What is a similarity between static and dynamic linkers?

Answer 10

they link external modules and libraries to main program

Question 11

What is a difference between static and dynamic linkers?

Answer 11

for static linkers:
- library code is copied into the file.
- the file size increases

for dynamic linkers:
- addresses of libraries are included within file.
- external updates are automatically fed through to main program

Question 12

What are 3 advantages of using libraries?

Answer 12

1. error- free
2. save time
3. reusable

Question 13

What is the function of a loader?

Answer 13

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

Question 14

What are the 3 purposes of the optimisation stage of compilation?

Answer 14

1. reduce execution time
2. reduce inefficient sections of code
3. remove redundant code