ZAX (The Glow)

ZAX is the machine intelligence controlling the facility at the Glow, developed by Vault-Tec. It is an advanced computer capable of learning, independent thought and creativity, with added error insertion to improve its variance in experience and learning capability. Initially a prototype of some of the systems designed to govern the vaults, it was given to the government to help the Department of Energy collect resource data. Within a year, it was taken by the military for plague and tactical research; one version, ZAX 1.2 was constructed for West Tek.

ZAX 1.2 was used at the West Tek facility for biological studies, including pathology and genetic research. Its primary function was in extrapolation of information of complexity levels exceeding human capacity. Its external functions, such as operating the labs, were crippled in the blast that hit the Glow, but it is otherwise intact. Its primary neural networking was initialized in 2053 by Justin Lee. The process of programming became largely irrelevant as it is capable of learning.

ZAX is also an avid, and very demanding chess player. To beat him, you need exactly 9 Intelligence (as described in Fallout Bible)

Other ZAX units
There are two other ZAX units in existence. ZAX-29 that was put in charge of Vault 29 instead of a human Overseer and the ZAX used at Boulder Dome.