The point inside the Earth where the movement from an earthquake first occurs is called the focus or hypocenter.

Here's a breakdown:

* Focus (Hypocenter): This is the exact point underground where the earthquake originates. It's where the built-up stress in the Earth's crust is suddenly released, causing the rocks to slip past each other.

* Epicenter: This is the point on the Earth's surface directly above the focus. It's the point where the earthquake's effects are typically felt most strongly.

So, the focus is the source of the earthquake, while the epicenter is the location on the surface where it's felt most intensely.