Acceleration is the rate of change of velocity, and velocity is a combination of speed and direction. So, something can be moving at a constant speed but still accelerating if its direction is changing.

Here's a classic example:

* An object moving in a circle at a constant speed.

Even though the object's speed might be constant, its direction is constantly changing, meaning its velocity is changing. Since acceleration is the rate of change of velocity, the object is accelerating.

Let me know if you'd like more examples!