* Immediately after being thrown: The ball has its maximum upward speed.

* As it travels upwards: Gravity acts on the ball, slowing it down. This means the ball's upward speed decreases.

* At the highest point: The ball momentarily stops moving, its upward speed reaches zero.

* As it falls back down: Gravity continues to act, now accelerating the ball downwards. The ball's speed increases as it falls.

In summary: The speed of a ball thrown upwards decreases as it goes up, reaches zero at its highest point, and then increases as it falls back down.