Embedded Linux
Linux is the operating system of choice for many embedded systems such as smartphones, tablets, PDAs, set-top boxes, and personal media players. Any version of Linux used to operate such machines is known as Embedded Linux. Linux is a natural choice for many of these devices due to its low cost and easy customization. It also has already been ported to custom-purpose microprocessors.
One major example of an embedded Linux is Android, developed by Google. Android is based on a modified Linux kernel and released under an open source license, which allows manufacturers to modify it to suit their particular hardware. Other examples of embedded Linux include Maemo, BusyBox, and Mobilinux. Debian, an open-source operating system which uses the Linux kernel, is used on the embedded Raspberry Pi device in an operating system called Raspberry.
Linux may require more system resources than other embedded operating systems but has a highly-tested stable kernel, is completely open source code, and a zero distribution cost.