Why did the old S go away? The answer lies largely in the use of the printing press. By the 1400s, a new set of S usage rules was established: The medial S would be used at the beginning of a lowercase word or in the middle of a word, while the round S would appear either at the end of a word or after a medial S within a word, as in “Congreſs” (which appears in the first line of Article I of the Constitution). But over time, the regular S, technically known as the “round S” or “short S,” started being used as a lowercase letter, too. Until around the 1100s or so, the medial S was the lowercase form of the letter, while the curvy line we use today was the uppercase form. The history of S is a twisting, turning path. It’s derived from the Roman cursive S, and it survived as the Old English S, then onward through the history of English orthography until the 1800s.

This old-fashioned letter has a long history. It’s actually a letter called the medial S, also known as the long S, which was a second form of the lowercase letter S. The answer lies in the fact that that’s not an F at all. Have you ever looked at a picture of a really old document or an inscription on the wall of an old building and thought, “Why are there F’s instead of S’s? Did F stand for S back then?” But no, it’s only some of the S’s that look like F’s, not all of them: You’ll see both letters right next to each other, so it’s not like they didn’t have the letter S back then.

Letters in old english font s