Gentoo may be installed in several ways. The most common way is to use the Gentoo minimal CD with a stage 3 tarball (see below for more explanation on stages). As with many Linux distributions, Gentoo may be installed from almost any Linux environment, such as another Linux distribution's LiveCD, LiveUSB or Network Booting using the Gentoo Alternate Install Guide. A normal install requires a connection to the Internet, but there is also a guide for a network-less install.
Previously, Gentoo supported installation from stage 1 and 2 tarballs. However, this is no longer recommended officially by the Gentoo foundation, and is meant only for Gentoo developers.
Following the initial install steps, the Gentoo Linux install process requires that all users compile their own Linux kernel. This process is generally not required by other Linux distributions. Although this is widely regarded as a complex task, Gentoo provides documentation and tools such as Genkernel to simplify the process and make it straightforward for novice users. Support for installation is provided on the Gentoo forum and on IRC.
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