Yes, the USAAF and the RAF both dropped them.

The usual purpose was to have the bomb penetrate, say, a building or an underground bunkerand then explode. However, if the bombs missed they laid and lay in wait for a specified time and then exploded. That's the theory.

In practice, the theory didn't hold up. Bombsights were well within the levels of accuracy that could be hoped for at the time, but the bombardiers were human. Humans can miss, especially when the plane is rocked by ack-ack, being attacked by other plances, etc. And in carpet bombing no accuracy is really expected -- just lay a carpet of bombs across a section of ground.

As the War went on bombs were more and more fitted with anti-movement devices. Move the bomb slightly, contacts close, and those nearby get harps and wings. Anti-lift devices were also built in so that a bomb could be cleared and then when it was lifted.... These devices were and are also used on land mines.   This was done by both sides.

To make matters worse, some of the explosives used (e.g., picric acid) can become very unstable after a period of time.

And still worse, it's estimated that 25 to 30 percent of all the ordnance used was defective.

It was also done in the Pacific. Japan, and especially on Okinawa, very often find such bombs. The island of Betio in the Tarawa atoll (now Kiribati) is another place. The Democratic Republic of the Congo, South Korea, Laos, Vietnam, Iraq...you can name more places.

Worldwide, the problem of UXO (UneXploded Ordnance) is tremendous. From rifle cartridges to bombs to cluster bombs to boobytraps to land mines, people are killed and injured every day by the "unexploded remnants of war". The UXO doesn't care what side you were on. They'll kill the winners as well as the losers and anyone else without care for civilian or combatant, young or old.