In the 18th and 19th centuries most infantry regiments or battalions had a "light company" as an integral part of its composition. Its members were often smaller, more agile men with high shooting ability and capability of using initiative. They did not usually fight in disciplined ranks as did the ordinary infantry but often in widely dispersed groups, necessitating an understanding of skirmish warfare. They were expected to avoid melee engagements unless necessary and would fight ahead of the mainline to harass the enemy before falling back to the main position.