7.1.3 Purpose and functions of software

• Operating systems come in many types and styles
• Name the 5 main types of OS:

  Batch OS

  Multi-tasking OS

  Real-time OS

  Network OS

  Mobile OS
• Batch OS is a simple OS that collects programs and data together before processing
• Batch OS process batches of data at regular intervals, irregardless of user input. It can be set to run at specific times making it useful as it can run at min processing times, but all batches are processed on a first-come-first-served basis
• Multitasking OS enable the use of a single computing resource for multiple uses at once
• Multitasking OS involves the processor handling multiple task at once, and is often used in larger more complex devices, especially those that people interact with. This makes it harder to set up, and needs more resources to handle.
• Real-time OS switches between tasks rapidly, giving the impression of all tasks being executed at the same time.
• Real-time OS is typically used within another application (embedded application) such as a smart home. In RTOS data is immediately processed when recieved leading to response times, and it can also priority schedule to ensure the most important data is processed first.
• RTOS will always produce the same output if the same input has been used. This is known as?


  Determinism
• Net OS are a very important type of OS that runs on a server and allows it use its resources for numerous in-built tasks (manage users, groups, data, etc)
• Net OSs are often stable, with responsibilities like security, remote access, and data storage
• Net OSs are expensive to purchase, and run; however upgrades are easier
• Mobile OSs have all that is required for mobile devices, and often provide platforms for other functions and features provided by software such as email, and online sync
• Name 3 mobile OSs:

  Andriod OS - google;open and free

  Apple OS - apple; secure and expensive; derived from Mac OS

  Windows mobile - Microsoft; cheap, versatile, compatible; based off windows CE 5.2
• What is middleware?

  Software between an OS and applications
• What is an IDE?

  Software with tools and functions for developers
• Utility software helps manage and maintain computers systems
• Microsoft has lots of utility software, such as disk management, disk cleanup, and task manager
• Application software are programs that help users complete tasks
• An example of application software is micrsoft word, so is adobe photoshop, and so is notepad
• Code development tools come in many shapes and sizes name the main one that most developers use and what it will have?

  IDEs

  Source code editor

  Compiler

  Debugger

  Assembler

  Linker
• What is a source code editor?

  text editor with extra features such as colouring of text based on type
• What is a compiler?

  Convertor of text of a certain programming language into another format, such as assembly
• What is a debugger?

  Tool that helps to consider any bugs in code, such as going one line at a time, or checking values of variables in real time
• What is an assembler?

  A program that converts assembly language (low-level) into machine code (lowest level)
• What is a linker?

  (sometimes link editor) Collects and maintains object files and combines them into a single executable