Understanding the role of Operating System

How does a computer work?



  • Operating System is the middle man between computer's hardware and the software applications that you run.
  • Whenever users want to perform any actions like Listen Music, Creating Documents, Video calls, etc - they use applications like VLC player to watch videos, Excel for documents, Skype for video calling, etc. Operating system allocates the hardware resources like Ram, HDD  for that application.
  • Operating System provides an interactive GUI through which user can perform their task.

 


What is a computer program?



  • If someone knows Japanese, then he/she can only communicate with another person only if they also know Japanese. For communication, we need a common language through which I can put my request and others will interpret that. If a german person talking to a French person then it is not possible to communicate unless they have something known as a translator.
  • Even the people who don't have any ability to speak, use sign language for communication. If the other side doesn't know the same language then communication is not possible.


  • A program is something like the language of a computer which a computer understands. There are many different programming languages like C, Java, Python, JavaScript , etc. Through Program, we can tell computers which task we want to perform. In our daily life, we use applications to perform some tasks like VLC for watching videos, Excel Sheet for documents, Skype for video calling, etc.
  • Every application in its core is a computer program, which is giving a nice beautiful interface through which we are communicating with the computers.

 

How do computers perform tasks?

  • To perform any task, we need 2 things 
    • The language that computers understand
    • Coding Environment
  • If you know any programming language then we can communicate with the computers but there is one more thing which is also needed that is the coding environment. Coding Environment is something on which we use to write and execute our programs.
  • Let's understand with an analogy :



  • Suppose If you are hungry, then we generally use to call our mother. If I am able to communicate to my mother that I am hungry and I need food. For ex:  you are desiring to eat idli, dosa, pav-bhaji, etc then my mother will understand what I actually want.
    • But to make this request successfully complete, Language is not just enough, we also need a kitchen where my mother can cook the food. Assume If I am on a trip with my family, During the travel, I put the desire of eating and I ask my mother to cook something then in that case it is not possible because there is no kitchen or you can say that there is no suitable environment.
    • In programming terms, writing JavaScript code in a text editor will not work, because JavaScript environment is not there.
    • Similarly, to run programs we need both Language and Coding environment.

 

Coding Environment




  • JavaScript is a scripting language and it runs on the browser.
  • Every Browser has an engine, which is responsible for running the JavaScript code and shows the required output.
  • Whenever you open any .js file from your browser, then browser process it automatically means the JavaScript engine present in the browser will execute that code and shows the respective results on the screen.

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