The one-handed American manual alphabet is a set of 26 manual alphabetical letters, corresponding to the English alphabet. It is used to fingerspell a string of the alphabetical letters of a certain English word, person's name, etc.
The American manual alphabet with a few modifications is derived from the French manual alphabet of the 18th century. Its cognates can be found in other signed languages' manual alphabets. For example, the German and American manual alphabets are similar; however, ASL and German Sign Language are completely different.