Operating system
Operating system or abbreviated as OS for computer programs. Without an operating system, users cannot run application programs on their computers, except the boot program.
1.Linux
.
Linux is a family of free and open-source software operating systems built around the Linux kernel. Typically, Linux is packaged in a form known as a Linux distribution for both desktop and server use. Wikipedia
2.MacOS.
macOS is a series of graphical operating systems developed and marketed by Apple Inc. since 2001. It is the primary operating system for Apple's Mac family of computers. Within the market of desktop, laptop and home computers, and by web usage, it is the second most widely used desktop OS, after Microsoft Windows. Wikipedia
3.Windows
.
Microsoft Windows is a group of several graphical operating system families, all of which are developed, marketed, and sold by Microsoft. Each family caters to a certain sector of the computing industry.Wikipedia 
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