system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How on earth do wells work?

I don't understand how do wells work. Like, I've seen a lot of wells made of stone, so, if you dig a huge hole in the ground, how does water come inside the well? Like, I've seen a lot of movies where someone gets stuck in a well or something, and there's always a rock bottom. So, how does water get inside the well?
gpt
In certain parts of the world, there is a layer of water saturating the ground under the surface. This is called the water table.

Pretend the water table is 9 meters below the surface.  If you then dig a hole 10 meters deep, it will penetrate the water table. Water will flow into the hole, filling it to a depth of 1 meter. Water then can be removed from the hole, which is now called a well.