Newton's Three Laws of Motion:
1. Law of Inertia: An object at rest stays at rest, and an object in motion stays in motion with the same speed and in the same direction unless acted upon by a net force.
2. Law of Acceleration: The acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass. This is often expressed as F = ma, where F is force, m is mass, and a is acceleration.
3. Law of Action-Reaction: For every action, there is an equal and opposite reaction.
These laws have been essential for understanding the motion of everything from planets to projectiles to cars. While advancements in physics, like Einstein's theory of relativity, have expanded our understanding of motion at extreme speeds and in strong gravitational fields, Newton's laws remain highly applicable in many everyday scenarios.