If I had to bet, I would say that @, or the at sign, is a recent addition to the symbols we use every day. But this NY Times blog post says I’m wrong. The symbol was first used by an Italian “in a letter written 473 years ago today, on May 4, 1536” (see the picture above). It was used then to indicate an ancient measure of weight or volume. The post is full of fun facts — such as the symbol is called a “snail” by Italians, and “monkey” or “dog” by Slavs.