Army uniform patches started as rank stripes. Eventually, commanders needed to know who they had in the field and who was that next to them. Soldiers designed patches and they were hand sewn together and quickly patches on the uniform became a thing. Every single Army unit in existence has a patch on their uniform that is worn with pride by the Soldier in that uniform. New units are formed and old ones are combined and absorbed to fill weakened areas and to fortify areas due to current trends. Old one as well and new patches are very collectible for their historical value and what it represents to the bearer.