1.2.2

• Application software or app software is category of software that allows...

  Users to accomplish tasks on a computer system
• Give 5 examples of utility software

  Anti-virus

  Fireball

  Compression

  Defrgamenter

  Disk clean up
• Utility software

  What is it

  Is a software that relates to the well being of your computer to keep it running smoothly and to keep it safe
• What are the 5 types of application examples:

  Web browsers

  Spreadsheet

  Gaming

  Presentations/slides show

  Social networking
• What is utility software designed for

  What is the one purpose it serves

  To keep it running smoothly and keep it safe

  Serve a disk defragmenter(organizes the individual files and improves hard drive speed)
• code generation

  what happens in this stage

  during this staage object or machine code is generated

  this is what the cpu actually works with to make your program run
• code optimisation

  what happens in this stage

  after code generation, it will be optimised for efficiency
• compiling a program

  when a code is being compiled through a ---, goes through -- stages

  -compiler

  4 stages
• in a syntax analysis what happens if a sectiom or part doesnt fit the rules

  an error is generated with detail of what and and where it is (if more is wrong then it will generate more errors)
• in code optimisation

  what is the purpose of optimising for efficiency

  purpose is to make the binary footprint as small as possible and will remove procedures and variables that are written into the code but never used
• in syntax analysis why does it differ to interpreted language

  becuase they return one error at a time
• lexical analysis

  white spaces(space added to seperate words) is needed in lexical analysis

  what does it help with

  it helps humans read the code,
• syntax analysis

  what happends inside them(in steps)

  -during the syntax analysis, tokenised code from lexical analysis is compared to the rules of the programming language
• what are the 4 stages of compiling, write in order

  -lexical analysis

  -syntax analysis

  -code generation

  -code optimisation
• what are the stages that go through inside a lexical analysis

  -it first checks for white space, it is removed firstly from the code because compilers dont need it

  -the compiler will then go through the code and create tokens out of the keywords and oepratros it finds(called lexemes)

  -it then puts it in a symbol table
• what is a token

  and example

  is a string that is recognized by the computer

  example: the number 8 will be assigned the token "number:8"
• back up software

  having lots of copies means what?

  that if something happened to one copy, we can restore it using the other
• back up software

  what is the purpose of back up software

  creates a copy of important data, so it can be stored in an external location
• Compression

  Compression utilities reduce the amount of disk space needed to store a file by applying

  What?

  A loseless compression algorithm
• Compression

  Uses of compression

  When can they be used

  When a file won't be accessed regularly, e.g, archives

  When a file is to be transferred on a network (to speed up the transfer)
• Compression

  What is loseless compression

  This means that no quality is lost from the original file and can be restored to the original
• Data compression and backup

  What does data compression allow

  Data compression software allows users to store more data onto a certain disk
• decompression

  -compression utuilities can also decompress the compressed files...

  -file must be decompressed in order to...

  -to return them to their original versions

  -in order to read them
• full back up

  what is an advantage and disadvantage

  advantage

  -easy to restore a system from a full back-up

  disadvantage

  -are a slow process and take up alot of space
• full back up

  what is it

  is where a copy is made of everything on the system onto the back up media
• incremental back-up

  advantage

  -much faster

  -use less space
• incremental back-up

  it is more difficult to restore system from incremental back-up because... (2 reasons)

  -the most recent full back up must be applied

  -every incremental back-up since then must be applied in the correct order
• incremental back-up

  what is it

  is where only the files that have changed since the last back up are closed
• Defragmentation software

  Deframentation

  Will increase the...

  Performance of the computer
• Defragmentation software

  Deframentation

  What does it do

  Recognizes the data on the storage device so that data from the same file is stored in the adjacent block
• Defragmentation software

  Fragmentation

  If a single file is stored in different places on a storage device, we say that the file is...

  Fragmented
• Defragmentation software

  Solid state drive(SSD)

  This provides random access to data. This means...

  That fragmentated data doesn't take longer to load
• Defragmentation software

  SSD

  SSD should never be defragmented because...

  this will push the device towards its read/write cycle limit, which shortens its lifetime
• Deframentation software

  Fragmentation

  What is wrong with fragmentation

  Fragmented file takes longer to load
• Encryption in generating system

  Good encryption utilities will work closely with the operating system to encrypt...

  And decrypt files in real time as you need to access them
• What is dcryption

  This is when an authorized party uses a special key to unscramble the data
• What is encryption

  This is the "scrambling" of data to protect sensitive data
• builtdynamically linked libraries

  is it bult into the code

  not built into the code
• dynamically linked libraries

  what does it mean

  mean your binary footprint is smaller, but the libraries need to be installed(unlike statically linked libaries)
• dynamically linked libraries

  when are these libraries loaded in

  when the object or machince code is passed to the CPU to run, just when it needs it