【Company】 , 【party】 , 【band】 , 【troop】 , 【troupe】 are comparable when they denote a group of persons who are associated in a joint endeavor or who are assembled for a common end.

【Company】 is the general term for either a temporary assemblage or a permanent association of individuals who join forces.

A  【party】 is a 【company】 assembled temporarily for a common purpose.

A 【band】 is a 【company】 united by a common tie or purpose; the term implies closer organization and a less casual coming together than does  【company】 .

A 【troop】 is a 【company】 or 【band】 that works or acts together in close formation or in unanimity; the term frequently suggests a throng or multitude.

In specific use 【troop】 is applied to a 【band】 of soldiers or, in the plural troops, to soldiers collectively.

When the reference is to a 【company】 of performers (especially on the stage), 【troupe】 is the preferred spelling.