How do satellites stay in orbit?

Satellites stay in orbit by balancing their forward velocity with Earth's gravity. They travel fast enough horizontally that as they "fall" toward Earth, the planet's surface curves away beneath them. Gravity provides the centripetal force that continuously pulls the satellite inward, causing it to follow a circular or elliptical path rather than flying off or crashing. In practical terms: a satellite accelerates during launch to orbital speed; once achieved, no extra thrust is needed (neglecting drag) and it will circle Earth indefinitely. If too slow, it falls back; if too fast, it escapes. The proper orbital velocity results in a stable orbit where gravity constantly bends the trajectory into a loop.