System Software:- The software that controls internal computer operations is called system software.
The System software can be classified into two categories:
1. Operating System 2. Language processor
Operating System: An operating System is a program which acts as an interface between a user and the hardware ( i.e all computer resources)
The operating system is an important component of a computer system which controls all other components of the computer system.
Types of Operating Systems:
1. Single Program OS- In this Operating System only one user program can be supported and executed by it at any point of time.
2. Multiprogram OS- It supports multiprogramming i.e., more than one programs are loaded and are active in the main store at the same time.
3. Time Sharing OS- A time sharing system allows many users to share the computer resources simultaneously. Each active user program is given a share of CPU time, if the time elapses, CPU shifts over to the next job waiting and previous program is put to wait.
4. Real Time OS- In real time OS, the jobs have fixed deadlines and the jobs have to be completed within their deadlines. A response time is pre determined. Each job is completed in a specified dead line.
5. Multiprocessing OS- The multiprocessing OS is capable of handling more than one processors as the jobs have to be executed on more than one processor.
Language Processors: It helps to convert Assembly language and High level language program into Low Level Language (Machine Language).
Types of Language processors:
Interpreter & Compiler.
Assembler- This Language processor converts assembly language into machine language.
Interpreter- This language processor converts High Level Language(HLL) program into Machine Language by converting and executing it line by line.
Compiler- This language processor converts HLL program into machine language . It converts the entire HLL program into machine language at one go.
Application software, also known as an application or an app, is computer software designed to help the user to perform specific tasks.
Application Software can further be subdivide into four categories-
1.) Packages 2.) Utilities 3.) Customised Software 4.) Developer Tools.
Packages- It is an Application software that are required to make the computer useful for people by handling a task.
General Application Software are known as Packages. Most commonly used packages are- word processors, spreadsheets, desktop publishing software, database management software, multimedia and presentation software.
- Word Processing Package is a package that processes textual matter and creates organized and flawless document. Eg., MS Word, Wordperfect , Softword .
- An Electronic Spreadsheet is a program that accepts data in a tabular form and allows user to manipulate/ calculate/ analyze data in the desired manner. Eg., Lotus 1-2-3, MS Excel, Quattropro .
- A Database Management System (DBMS) is a package that can handle and manage bulk of stored data. Eg., MS Access, Oracle, MySQL .
- Desktop Publishing Software handles layout by combining the functions of a traditional typesetter and a layout artist.
- The application software that manipulates images is known as Graphics Software and the software that incorporates images, text, sound, computer animation and video is known as multimedia software.
Utility program:Utility Program assist the computer in maintaining its performance.
Some utility programs are- text editor, backup utilities, compression utilities, disk defragmentors and antivirus software.
Some Utility programs:
Compression Tools: They are used to Compress Data in the computer system.
Advantages of data compression are that compressed data will take up less space on a computer and be quicker to transmit. Ex: 7-Zip, IZArc, WinRAR, PeaZip, The Unarchiver.
Disk Defragmenter:Disk Defragmenter is a utility in Microsoft Windows designed to increase access speed by rearranging files stored on a disk to occupy contiguous storage locations, a technique called defragmentation. Disk Defragmenter also reduces system startup times.
Antivirus:Antivirus or anti-virus software is software used to prevent, detect and remove malware such as: computer viruses, adware, spyware, trojan horses and worms. Commonly used Antivirus are Norton, Kaspersky, Quick heal etc.
Customised Software- They are tailor made software according to user’s requirements.
Developer Tools- Developer Tools are tools that are needed to develop a software for any type of application. Some commonly used developer tools are – Compilers, Interpreters, Integrated Development Environment (IDE).
Integrated Development Environment (IDE) is an application program consisting of different development tools needed for developing an application.