Squad (land forces)
A squad is the basic unit for infantry military tactics, composed of 7-13 infantrymen or other combat specialists, and subdivided into two or more fire teams. Usually, they are led by a non-commissioned officer, typically a mid-level sergeant.
Squads combine into platoons, which are the first level normally commanded by an commissioned officer. Some armies have an intermediate level of section between platoon and squad. Infantry squads are pure fighting units, with no dedicated supply or maintenance resources. Their first level of supply comes from the company, usually two hierarchical levels above a squad.
The basic infantry squad is also called a rifle squad, as most of its members are armed with an assault rifle. The squad usually has one to three light machine guns. Soldiers may also carry lightweight anti-tank weapons, which are often disposable unguided rockets. Most soldiers carry hand-thrown grenades and some may have grenade launchers.
There are other kinds of squads, still principally front-line combat units, such as combat engineers. Not all combat units of comparable size are called squads. In United States Army Special Forces, the basic A detachment has 12 soldiers, but is intended for independent operations, and is commanded by a captain rather than a sergeant. Support units of similar size are more apt to be called sections, teams, cells, or detachments.