The Bureau of Printing and Engraving prints money, but Federal Reserve Notes are in fact a claim on bank reserves. It's just when you deposit them at your bank

The Bureau of Printing and Engraving prints money, but Federal Reserve Notes are in fact a claim on bank reserves. It's just when you deposit them at your bank you don't get reserves, they instead create a bank deposit for you and a liability for them and then add the reserves you just gave them to THEIR account.