Military term, a squad is usually devided into fireteams (usually with 4 men each) and a Squad leader to command them.

Here is an example of a 11-man squad (in this example, Fireteam Green is a sharpshooter team):

-Squad lead

Fireteam Red
-Red lead
-Rifleman one
-Rifleman two
-Rifleman three

Fireteam Blue
-Blue lead
-Rifleman four
-Rifleman five
-Rifleman six

Fireteam Green
-Spotter and Green lead
-Advanced Marksman

Please note that certain terms etc. may differ between units. Eg, instead of Red, Blue etc. the fireteams may be designated Alpha, Bravo etc.