In matchbook-collecting circles, front-strikers have the striking surface on the front next to the exposed matches. Back-strikers have the striking surface on the back, away from the matches. The front-to-back migration is to comply with a 1973 federal safety regulation.

Via Eric Scheie, who tested old and new matches to confirm his suspicion that newer matches don't burn as well as the old ones. In his test they didn't. That's also likely due to a federal regulation, this time from 1976, that requires "the flame must self-extinguish within 12.7 mm (0.5 inches) down from the top of the match and within a 15-second period."