Gentoo is a computer operating system built on top of the Linux kernel and based on the Portage package management system. It is distributed as free and open source software, but includes some proprietary software packages.
Unlike a conventional software distribution, the user compiles the source code locally according to their chosen configuration.
Gentoo is based on a rolling release principle: once installed, a system can be upgraded package by package. Although Gentoo releases originally existed in the form of installation media, since 2008, installation media are regenerated every week.