From this post, I noticed today was the Armor Birthday – https://history.army.mil/faq/branches.htm. I used the link found here: Some Various Army Units Birthdays April 27, 2020. I am not going to count 1776 as the birthday as armor hasn’t been around that long and will do another post on July 10, 2021 as the official birthday post. I am not going to argue with the U. S. Army as the first link is from their website.
From the first link:
Armor, December 12, 1776
The Armor branch traces its origin to the Cavalry. A regiment of cavalry was authorized to be raised by the Continental Congress Resolve of December 12, 1776. Although mounted units were raised at various times after the Revolution, the first in continuous service was the United States Regiment of Dragoons, organized in 1833. The Tank Service was formed on March 5, 1918. The Armored Force was formed on July 10, 1940. Armor became a permanent branch of the Army in 1950.
While the armor has a different birthday on Wikipedia as July 10, 1940: https://en.wikipedia.org/wiki/Armor_Branch. I went with the first link above as that has it with the December 12th birthday.