The theory of relativity, developed by Albert Einstein, revolutionized our understanding of space, time, and gravity. It comprises two main theories: Special Relativity and General Relativity.

1. Special Relativity:
   • Time Dilation: Time is not absolute; it can dilate or contract based on an observer’s relative motion.
   • Length Contraction: Objects appear shorter when moving at high speeds.
   • E=mc²: Energy (E) is equivalent to mass (m) times the speed of light (c) squared.
2. General Relativity:
   • Curvature of Spacetime: Massive objects, like planets, create curves in the fabric of spacetime, affecting the motion of other objects.
   • Gravity as Warping: Gravity is not a force but a result of the curvature of spacetime caused by mass.
   • Time Dilation in Gravity: Clocks in stronger gravitational fields tick more slowly.

Einstein’s theories have been confirmed through experiments and observations, demonstrating that our perception of reality is intricately linked to the fabric of spacetime itself.