1.2.2. Applications Software

What is the difference between applications and systems software?

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

Give 3 examples of utilities

• Compression
• Disk defragmentation
• Antivirus
• Word Processor
• Presentation Software

Give advantages of using closed source code

• 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

• Distributed with the source code

• Can be modified and sold on

State features of open source code

• Does not require a license to be used
• Distributed with the source code
• Can be modified and sold on
• Thorough, regular and well-tested updates
• High levels of security as it is developed in a professional, controlled environment

Give two advantages of using compiled code over interpreted code

• Faster to execute
• Does not require compiler to run
• Is platform independent
• Runs instantly without time waiting for compilation

Identify advantages of using interpreted code over compiled code

• Is platform independent

• Runs instantly without time waiting for compilation

• Faster to execute

• Does not require compiler to run

What is assembly language?

• A low-level language that has almost a one-to-one relationship with machine code. It is platform specific.
• a computer programming language consisting of binary or hexadecimal instructions which a computer can respond to directly.
• a programming language with strong abstraction from the details of the computer

What are the stages of compilation?

• Lexical analysis
• Syntax analysis
• Code generation
• Optimisation
• Completion

What happens during syntax analysis?

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

What are the similarities between static and dynamic linkers?

• Both link external modules and libraries to main program
• Library code copied into the file. File size increased
• Addresses of libraries included within file. External updates automatically feed through to main program.