Installation

The system requirements vary among Ubuntu products. For the Ubuntu desktop release 16.04 LTS, a PC with at least 2 GHz dual core processor, 2 GB of RAM and 25 GB of free disk space is recommended.^[43][44] For less powerful computers, there are other Ubuntu distributions such as Lubuntu and Xubuntu. Since version 12.04, Ubuntu supports the ARM architecture.^{[2][45][46][47][48]} Ubuntu is also available on Power,^{[2][49][50][51]} older PowerPC architecture was at one point unofficial supported,^[52] and now newer Power Architecture CPUs (POWER8) are supported.
Live images are the typical way for users to assess and subsequently install Ubuntu. These can be downloaded as a disk image (.iso) and subsequently burnt to a DVD and booted, or run via UNetbootin directly from a USB drive (making, respectively, a live DVD or live USB medium). Running Ubuntu in this way is typically slower than running it from a hard drive, but does not alter the computer unless specifically instructed by the user. If the user chooses to boot the live image rather than execute an installer at boot time, there is still the option to then use an installer called Ubiquity to install Ubuntu once booted into the live environment.^[53] Disk images of all current and past versions are available for download at the Ubuntu web site.^[54] Various third-party programs such as remastersys and Reconstructor are available to create customized copies of the Ubuntu Live DVDs (or CDs). "Minimal CDs" are available (for server use) that fit on a CD.
Additionally, USB flash drive installations can be used to boot Ubuntu and Kubuntu in a way that allows permanent saving of user settings and portability of the USB-installed system between physical machines (however, the computers' BIOS must support booting from USB).^[55] In newer versions of Ubuntu, the Ubuntu Live USB creator can be used to install Ubuntu on a USB drive (with or without a live CD or DVD). Creating a bootable USB drive with persistence is as simple as dragging a slider to determine how much space to reserve for persistence; for this, Ubuntu employs casper.^[56][57]
The desktop edition can also be installed using the Netboot image (a.k.a. netboot tarball) which uses the debian-installer and allows certain specialist installations of Ubuntu: setting up automated deployments, upgrading from older installations without network access, LVM and/or RAID partitioning, installs on systems with less than about 256 MB of RAM (although low-memory systems may not be able to run a full desktop environment reasonably).^[58]