* Forces and Motion: Forces cause changes in motion. This means they can start something moving, stop something moving, or change the direction of something moving.

* Balanced Forces: When an object is stationary (not moving), it means the forces acting on it are balanced. This means there are equal forces pushing or pulling in opposite directions, canceling each other out.

Examples:

* A book on a table: Gravity is pulling the book down, but the table is pushing back up with an equal and opposite force. The book is still, even though forces are acting on it.

* A person standing still: The force of gravity pulls the person down, but the ground pushes back up with an equal force.

Important Note: An object can be stationary for a short period even with unbalanced forces. Imagine pushing a heavy box. You apply a force, but it doesn't move right away. This is because the static friction between the box and the floor is initially strong enough to counteract your force. But if you push hard enough, you overcome the friction and the box will move.