Friction opposes motion. It doesn't have a direction of its own, but rather acts in the opposite direction to the intended motion.

Here's a breakdown:

* Sliding friction: If you push a box across the floor, friction acts in the opposite direction of your push, slowing the box down.

* Rolling friction: If you roll a ball, friction acts against the rolling motion, eventually bringing the ball to a stop.

* Fluid friction: As an object moves through a fluid (like air or water), friction acts against the object's movement, slowing it down.

In summary, friction's direction is always opposite to the direction of motion or the intended motion.