Linux kernel

Linux kernel is probably the most important part of a Linux system. It bridges the gap between computer hardware and software, it makes hardware resources available to other applications.

Linux kernel is responsible for:

Process management. It makes sure proper allocation of system’s hardware resources to software.

Memory management. It not only allocates physical memory to a software, but also responsible for allocating swap space. Swap space is disk memory file that can be used as additional memory in a system.

Device management. It allows physical devices to communicate with the rest of the system as well as allows system to communicate with this device.

System calls. System calls allow software to use hardware resources allocated. An example of a system call is opening a file in a hard drive.

It is responsible for system’s security. It ensures that a specific program can only access system’s resources allocated to it. An application cannot arbitrarily start using system’s resources that had been allocated to another application.

It also allows software to establish network connections.

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