A launcher is a device that propels or releases something into motion. The most familiar kind might be a toy rocket launcher that sends a foam rocket flying across the backyard when you stomp on its air pump. Military forces use missile launchers to fire rockets, and spacecraft sit atop massive launchers that thrust them toward orbit.

But launcher has another common meaning in technology. A launcher is also a program that helps you open and organize other programs on your computer or phone. When you tap an icon on your tablet's home screen, you're using the launcher to start that app. Think of it as the control panel that helps you access everything else, like a hallway with doors leading to different rooms.

The word suggests something that initiates action or gets things started. A baseball pitching machine is sometimes called a ball launcher. A trap launcher in shooting sports flings clay disks into the air. Whether it's sending a satellite into space or simply opening your favorite game, a launcher's job is to set something in motion.