While a serger and an overlocker may sound like two different things, they are not. Sergers can perform overlock stitching, so they were called overlockers when they were first invented in 1889. This term is still used in some parts of the world, but in the United States, the machine is called a serger. The terms serger and overlocker can be used interchangeably. You might also notice a serger called an overlock machine.