Whether it’s called an “octothorpe,” “pound,” “hashtag,” or “number” sign, the # symbol originated as the abbreviation “lb” (for the Latin “libra pondo,” or “pound weight”). The handwritten “lb” often looked like a messy scrawl of four crossed lines, and an official symbol was derived from that. AT&T added the symbol, along with the asterisk (*), to its touch-tone telephone in 1968 in order to make the keypad square. The origin of the word “octothorpe” is uncertain, though the term was in use at Bell Telephone Labs by the early 1970s, and most believe it was coined by Bell Labs employee Don MacPherson. The story goes that MacPherson combined the Latin prefix “octō-,” meaning “eight,” with the proper name Thorpe in homage to American gold-medal Olympian and football player Jim Thorpe.