Bare Metal
A bare metal system is a computer that does not include any software. This means the user must install an operating system in order for the hardware to be functional.
The term "bare metal" is commonly used to refer to custom-built PCs and barebones systems. These types of computers are ideal for PC enthusiasts, who may prefer to install their own software rather than paying extra for pre-loaded programs. A bare metal system also allows advanced users to choose a non-mainstream OS, such as a specific Linux distribution.
Web hosting companies may also offer bare metal systems to clients who wish to customize their web server from the ground up. For instance, a client may purchase a dedicated or co-located server with a specific hardware configuration. The server administrator can then install a specific operating system and web server software on the computer.
NOTE: Bare metal is sometimes used to refer to a "bare metal restore," which refers to restoring a complete computer software configuration.