On our last lesson, I was able to take you through the knowledge base step by step guide to computer booting in our modern African technology. Today, I am happy to see us go through computer operating system in details.
An operating system (OS) is system software that manages computer hardware, software resources, and provides common services for computer programs. … Operating systems are found on many devices that contain a computer – from cellular phones and video game consoles to web servers and supercomputers.
An Operating System (OS) is an interface between a computer user and computer hardware. An operating system is a software which performs all the basic tasks like file management, memory management, process management, handling input and output, and controlling peripheral devices such as disk drives and printers.
Software required to run the hardware parts of the computer and other application software are called system software. System software acts as interface between hardware and user applications. An interface is needed because hardware devices or machines and humans speak in different languages.
Machines understand only binary language i.e. 0 (absence of electric signal) and 1 (presence of electric signal) while humans speak in English, French, German, Tamil, Hindi and many other languages. English is the pre-dominant language of interacting with computers. Software is required to convert all human instructions into machine understandable instructions. And this is exactly what system software does.
Based on its function, system software is of four types −
- Operating System
- Language Processor
- Device Drivers
System software that is responsible for functioning of all hardware parts and their interoperability to carry out tasks successfully is called operating system (OS). OS is the first software to be loaded into computer memory when the computer is switched on and this is called booting. OS manages a computer’s basic functions like storing data in memory, retrieving files from storage devices, scheduling tasks based on priority, etc.
As discussed earlier, an important function of system software is to convert all user instructions into machine understandable language. When we talk of human machine interactions, languages are of three types −
- Machine-level language − This language is nothing but a string of 0s and 1s that the machines can understand. It is completely machine dependent.
- Assembly-level language − This language introduces a layer of abstraction by defining mnemonics. Mnemonics are English like words or symbols used to denote a long string of 0s and 1s. For example, the word “READ” can be defined to mean that computer has to retrieve data from the memory. The complete instruction will also tell the memory address. Assembly level language is machine dependent.
- High level language − This language uses English like statements and is completely independent of machines. Programs written using high level languages are easy to create, read and understand.
Program written in high level programming languages like Java, C++, etc. is called source code. Set of instructions in machine readable form is called object code or machine code. System software that converts source code to object code is called language processor. There are three types of language interpreters−
- Assembler − Converts assembly level program into machine level program.
- Interpreter − Converts high level programs into machine level program line by line.
- Compiler − Converts high level programs into machine level programs at one go rather than line by line.
System software that controls and monitors functioning of a specific device on computer is called device driver. Each device like printer, scanner, microphone, speaker, etc. that needs to be attached externally to the system has a specific driver associated with it. When you attach a new device, you need to install its driver so that the OS knows how it needs to be managed.
A software that performs a single task and nothing else is called application software. Application software are very specialized in their function and approach to solving a problem. So a spreadsheet software can only do operations with numbers and nothing else. A hospital management software will manage hospital activities and nothing else. Here are some commonly used application software −
- Word processing
- Database management
- Multimedia tools
Application software that assist system software in doing their work is called utility software. Thus utility software is actually a cross between system software and application software. Examples of utility software include −
- Antivirus software
- Disk management tools
- File management tools
- Compression tools
- Backup tools
Features of the operation system
- Keeps all hardware parts in a state of readiness to follow user instructions
- Co-ordinates between different devices
- Schedules multiple tasks as per priority
- Allocates resource to each task
- Enables computer to access network
- Enables users to access and use application software
Besides initial booting, these are some of the functions of an operating system −
- Managing computer resources like hardware, software, shared resources, etc.
- Allocating resources
- Prevent error during software use
- Control improper use of computer
Popular Operating Systems
Initially computers had no operating systems. Every program needed full hardware specifications to run correctly as processor, memory and device management had to be done by the programs themselves. However, as sophisticated hardware and more complex application programs developed, operating systems became essential. As personal computers became popular among individuals and small businesses, demand for standard operating system grew. Let us look at some of the currently popular operating systems −
- Windows − Windows is a GUI operating system first developed by Microsoft in 1985. The latest version of Windows is Windows 10. Windows is used by almost 88% of PCs and laptops globally.
- Linux − Linux is an open source operating system mostly used by mainframes an supercomputers. Being open source means that its code is available for free and anyone can develop a new OS based on it.
- BOSS − Bharat Operating System Solutions is an Indian distribution of Linux based on Debian, an OS. It is localized to enable use of local Indian languages. BOSS consists of −
- Linux kernel
- Office application suite BharteeyaOO
- Web browser
- Email service Thunderbird
- Chat application Pidgim
- File sharing applications
- Multimedia applications
An operating system for smartphones, tablets and other mobile devices is called mobile OS. Some of the most popular OS for mobile devices includes−
- Android − This Linux-based OS by Google is the most popular mobile OS currently. Almost 85% of mobile devices use it.
- Windows Phone 7 − It is the latest mobile OS developed by Microsoft.
- Apple iOS − This mobile OS is an OS developed by Apple exclusively for its own mobile devices like iPhone, iPad, etc.
- Blackberry OS − This is the OS used by all blackberry mobile devices like smartphones and playbooks.
Application software that assist OS in carrying out certain specialized tasks are called utility software. Let us look some of the most popular utility software.
Antivirus software, or antivirus software, also known as anti-malware, is a computer program used to prevent, detect, and remove malware. Antivirus software was originally developed to detect and remove computer viruses,
A software that assists the OS in providing virus free environment to the users is called antivirus. An anti-virus scans the system for any virus and if detected, gets rid of it by deleting or isolating it. It can detect many types of virus like boot virus, Trojan, worm, spyware, etc.
When any external storage device like USB drive is attached to the system, anti-virus software scans it and gives an alert if a virus is detected. You can set up your system for periodic scans or scan whenever you feel the need. A combination of both the techniques is advisable to keep your system virus free.
File management tools
File Management: The process and act of creating an organized structure in which you store information for easy retrieval.
File management is an important function of operating systems as all data and instructions are stored in the computer in form of files. Utility software providing regular file management tasks like browse, search, update, preview, etc. are called file management tools. Windows Explorer in Windows OS, Google desktop, Directory Opus, Double Commander, etc. are examples of such tools.
A compression program or compression utility is a software program that compresses and decompresses various file types. It can reduce the size of a file.
some examples are:
- Zip Archiver.
Disk cleanup tools assist users in freeing up disk space. The software scans hard disks to find files that are no longer used and frees up space by deleting them.
Disk defragmenter is a disk management utility that increases file access speeds by rearranging fragmented files on contiguous locations. Large files are broken down into fragments and may be stores in non-contiguous locations if contiguous ones are not available. When such files are accessed by the user, access speed is slow due to fragmentation. Disk defragmenter utility scans the hard disk and tries to assemble file fragments so that they may be stored in contiguous locations.
Backup utility enables backing up of files, folders, databases or complete disks. Backups are taken so that data may be restored in case of data loss. Backup is a service provided by all operating systems. In stand-alone systems backup may be taken in the same or different drive. In case of networked systems backup may be done on backup servers.
on our next lesson would be