Intro to Linux

Learn about one of the most popular, robust and free operating system out there!

What is Linux ?

Linux is open-source Unix like operating system based on the Linux Kernel. It was developed by Linus Torvalds in early 1990.

All the hardware needs an Operating System (aka OS) to communicate with the hardware resources. Without a suitable OS hardware wouldn't know what to do.

Just like any other operating system Windows, Mac OS, iOS, Linux is an OS which let you take advantage of the hardware resources, like RAM, CPU, Graphics card and other peripherals.

An open source operating system source code is publicly visible for any developers fix any bugs and make any improvement to the code . In contrast, the close operating system are Microsoft's Windows, Apple's iOS and Mac OS. All the source codes are kept away from users.

The operating systems are made of many components, but the prime components are

• Kernel
• Shell

Shell pass the user commands from Terminal to Shell, which then passed to Kernel. Kernel acts like a error checking mechanism that checks the commands prior to executing the code on the hardware.

The above diagram shows how does user input get executed through Terminal, also known as Command Line Interface (CLI). Whenever you type a command to CLI, this would communicate with the Shell to execute the task through OS, then Kernel.

The Kernel is the core of the system that manages CPU, Memory, and other peripheral devices. It's the lowest level of the OS that talks to hardware.

The diagram above shows how the Firefox program is executed through Terminal command. Commands are executed in Terminal, which talks to Shell, that make use of hardware resources to open the program.

What is the difference between Unix and Linux ?

Unix is a multitasking, multiuser computer operating system, developed in 1969. it was first used in Mainframe, enterprise and universities. When a young Computer scientist named Linus Torvalds worked with Unix, he suggested improvements to the Unix, but it was rejected.

Linus decided to develop his own operating system called Linux that is receptive to changes, modifications suggested by its users. In early 1990 he created an Linux Operating System which is used by millions of people today, and other big organisations.

Since the Linux is an open source operating system, allowing other users to create customisable operating system based on their needs using Linux Kernel. These are called Linux Distributions (aka Distros or Flavours).

Here are some of the Linux flavours you can try out in an isolated environment without messing up your primary OS. You can find a guide how to set-up your own Pen testing lab here

What are the advantages of using Linux OS ?

Linux is distributed under an open source  license. This means you can learn how the software is structured and developed from the source code, re-distribute copies of the programs to your friends and families. Create your own version of Linux, thus we have 600+ Linux flavours to choose from.

Reasons to love Linux

• Open Source             Free for anyone to use, check source code
• Big Community           Great Community of users & developers
• Customisable OS        Fully customisable for hardware needs
• Reliable + Stable OS           Runs for years without needing to reboot
• Less venerable to Malware      Anti-Virus is not required

Why you should learn Linux ?

One of the great Operating System made by man kind and it's free! It's currently powering majority of the servers, desktops, and mainframes.