Linux is an open-source, Unix-like operating system kernel first created by Linus Torvalds in 1991.
It serves as the core component of various Linux distributions, which are complete operating systems that include the Linux kernel along with supporting system software and libraries.
Key characteristics of Linux include:
1. Open Source: Linux is distributed under open-source licenses, allowing users to view, modify, and distribute the source code.
2. Multiuser: Linux supports multiple users working on the system simultaneously, each with their own user account and privileges.
3. Multitasking: It can perform multiple tasks simultaneously, allowing efficient use of system resources.