Forward Operating Base
From Halopedia, the Halo wiki
A Forward Operating Base or FOB is a general term used to describe any secured military position established for the purposes of supporting strategic and/or tactical goals on a battlefield.
During the Installation 07 conflict, the surviving UNSC personnel from the UNSC Infinity set up at least twelve Forward Operating Bases on the fragmented section of Zeta Halo. However, by March 3rd, 2560, all twelve FOBs had fallen into Banished hands. They would remain that way until May 28, 2560, when John-117 arrived on the Ring and began retaking the FOBs, starting with FOB Golf.
In Halo Infinite
There are a total of twelve FOBs that can be recaptured. Once captured, they can be used to summon weapons, vehicles, and marine reinforcements. They can also be used for fast travel. Capturing a FOB will also reveal additional targets in the surrounding area.
The FOBs are:
List of appearances