1.2.2 Applications generation

Question 1

What is a utility?

Answer 1

Utility software includes all systems and programs on a computer system that maintain its functionality.

Question 2

Name 5 types of utility software?

Answer 2

File repair
Backup
Data compression
Defragmentation
Anti-malware

Question 3

What does defragmentation software do?

Answer 3

Defragmentation reorganises files on a hard disk. putting fragments of files and free space back together

Question 4

Define open source software?

Answer 4

Open source code can be used by anyone without a license and is distributed with the source code.

Question 5

Define closed source software?

Answer 5

Closed source code requires the user to hold an appropriate license to use it. Users cannot access the source code as the company owns the copyright license.

Question 6

Give 2 advantages of open source software?

Answer 6

Can be modified and improved by anyone
Technical support from online community

Question 7

Give a disadvantage of open source software?

Answer 7

Lower security as may not be developed in a controlled environment

Question 8

Give 2 advantages of closed software?

Answer 8

Thorough, regular and well-tested updates
High levels of security as developed professionally.

Question 9

Give a disadvantage of closed software?

Answer 9

Users cannot modify and improve software themselves

Question 10

What is a translator?

Answer 10

A translator is a program that converts high-level source code into low-level object code

Question 11

What are the 3 types of translators?

Answer 11

Compiler
Interpreter
Assembler

Question 12

What is a compiler?

Answer 12

A compilers translate high-level code into machine code all at once, after carrying out a number of checks and reporting back any errors.

Question 13

What is a interpreter?

Answer 13

Interpreters translate and execute code line-by-line. They stop and produce an error if a line contains an error.

Question 14

What is a assembler?

Answer 14

Assembly code is considered to be a low-level language as it is the ‘next level up’ from machine code.

Question 15

Name 2 advantages of using a compiler?

Answer 15

Compiled code tends to run faster than interpreted code because it has been translated into machine code that can be directly executed by the computer’s processor
Compilers allow programmers to write code in a high-level programming language that can be easily translated into machine code for a variety of different platforms.

Question 16

Name 2 disadvantages of using a compiler?

Answer 16

Compilation can take a significant amount of time.
If changes need to be made, the whole program must be recompiled.

Question 17

Name 2 advantages of using a interpreter?

Answer 17

Executes line by line. Hence, debugging is easy.
No intermediate code hence uses the memory efficiently

Question 18

Name a disadvantages of using a interpreter?

Answer 18

Execution time is more.

Question 19

What are the four stages of compilation in order?

Answer 19

1. Lexical analysis
2. Syntax analysis
3. Code generation
4. Code optimisation

Question 20

What 2 steps happen in lexical analysis?

Answer 20

1. Whitespace and comments are removed from the code
2. The remaining code is analysed for keywords and names of variables and constants, these are replaced with tokens and information about the token associated with each keyword or identifier is stored in the symbol table.

Question 21

What 2 steps happen in syntax analysis?

Answer 21

Tokens are analysed against the grammar and rules of the programming language. Any tokens that break the rules of the programming language are flagged up as syntax errors and added to a list of errors.
An abstract syntax tree is produced, which is a representation of the source code in the form of a tree.

Question 22

What step happens in Code generation?

Question 23

What is a linker?

Answer 23

This is a piece of software that is responsible for linking external modules and libraries included within the code.

Question 24

What are the 2 different types of linkers?

Answer 24

Static
Dynamic

Question 25

Describe a static linker?

Answer 25

Modules and libraries are added directly into the main file.

Question 26

Describe a dynamic linker?

Answer 26

Addresses of modules and libraries are included in the file where they are referenced. When the program is run, the loader retrieves the program at the specified address so it can be executed.

Question 27

What is a loader?

Answer 27

Loaders are programs provided by the operating system. When a file is executed, the loader retrieves the library or subroutine from the given memory location.