Software and Software Development

Software and Software Development

1. Sytem software

   • Functions of OS
     • Memory Management
       • Pageing
         • Physical Devion
         • Same Size
       • Segmention
         • Logical Devsion
         • Diffrent size
       • Virtual memory
     • Backing Management
       • Transfer between main memory and Secondery storage
     • Interrupts Service routine
       • Stack
       • Higher level
     • Input / Output Management
     • Secduling
   • Types of OS
     • Real time
       • Respond in set time frame
       • Constant updates
     • Distbuite
       • This is a type of operating system which is run across multiple devices, allowing the load to be spread across multiple computer processors when a task is run.
     • Multistaking
       • Time slice
     • Emmbeded
       • Built to perform a small range of specific tasks
       • Less power
     • Multi User
   • BIOS
     • First Program
     • Key tests
   • Device Drivers
     • allow the operating system to interact with hardware

2. Applications Generation

   • Types of software
     • Sytems
       • low-level software that is responsible for running the computer system smoothly
     • Application
       • used by the end-user to perform one specific task
   • Utillty
     • Anit virus
       • Detects threast to computer system
     • Automatic updating
       • Keeps OS up to date
     • Disk Defrag
       • re oders hard drive so space is used effiecntly
     • Compression
       • Makes data smaller
     • Backup
     • Needed for consistent, high performance of the operating system. Each utility program has a specific function linked to the maintenance of the operating system.
   • Open / Closed
     • Open distributed with the source code.
     • 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.
   • Translators
     • Types
       • Assmbler
         • 1 to 1
       • Interprter
         • line by line
       • Complier
         • All in one
     • Stages of compilation
       • Optimiastion
         • Makes code run faster
         • redundant parts of code are detected and removed
       • Code Generation
         • Syntax anlsis used to produce a code
       • Syntax Analysis
         • Semantic analysis
           • Logical check
         • Tokens are anlyised
         • Syntax flagged
       • Lexical Analysis
         • Superflow
         • tokens
   • Linker, Loaders , libarys
     • Loader
       • loader retrieves the library or subroutine from the given memory location
     • Libarys
       • pre-compiled programs
       • error free, ready to use
     • Linker
       • linking external modules and libraries included within the code.

3. Programming methodologies

   • Methods
     • waterfall
     • Agile
     • Extreme Programming
     • Spiral
     • Rapid Application Development
   • Stages
     • Analsis
       • clearly define the problem
       • stakholders
     • Desigen
       • test plan
     • Development
       • Indavidule modules
     • Implementation
       • installed onto the users’ systems
     • Evaluation
       • effectiveness of the software
     • Testing

4. Types of Programming Language

   • Programming paradigms
     • Decletive
       • Functional
         • Re using a set of fucnctions
         • linked to maths
       • Logic
         • Quires
         • set of facts and rules
     • Imperative
       • Procedural
         • sequence of instructions
         • Sequnce,selction,ittration,recusion
       • Object-Oriented
         • objects formed from classes which have certain attributes and methods
         • class
           • template for object
         • attribuits
           • proprites
         • metods
           • actions that are preformed
         • Polymorphism
         • Encapuslaiton
         • Intitaison
         • inheritance
   • Modes of addressing