Linux Operating System
Why Linux?
Linux is free and open source, you can see the source code used to create Linux (kernel).
Linux is Unix-based and Unix was originally designed to provide an environment that is powerful,stable,reliable yet easy to use. Linux systems are widely known for their stability and reliability, many Linux servers on the internet have been running on the internet for many years without failure or even being restarted.
Why Linux is better than WINDOWS for Servers?
Linux is without doubt the most secure kernel out there, making Linux based OS secure and suitable for servers.
Since Linux is Open source so it’s so powerful and flexible. You can tune it to meet your server needs. It allows you to do whatever you want (if possible).
You can install a GUI (graphical user interface) or simply operate your server via a terminal only.
The total cost of owning and maintaining a Linux server is lower as compared to a Windows server, in terms licensing fees , software/hardware purchase, maintenance costs, system support services and administrative cost.
What is Linux?
An Open source OS modelled on UNIX. Just like Windows XP, Windows 7, Windows 8, and Mac OS X, Linux is an operating system.
The OS manages the communication between your software and your hardware. Without the operating system the software wouldn’t function.
What is Kernel?
Kernel is a core component of operating system. Kernel works as a “Bridge” between hardware and application.
System memory or main memory is divided into 2 parts.
- Kernel space
- User space
In User space , the process of applications like video player, audio player are supposed to run. If we want to run the user applications , we need a Kernel space/ Kernel mode Since we need a hardware to execute the application.
One of the roles of the kernel is to manage individual user processes within this space and to prevent them from interfering each other.
Kernel space can be accessed by user processes only through the use of system calls. System Calls are written in C language. There’s a library , named “GNU C Library” which is also for system calls.
There are multiple functions which are written in GNU C Library (eg: Chmode, Sudo) through which we can access user space to kernel space.
