ELI5: How is fog different from clouds?

Imagine you're blowing bubbles at a playground.

Clouds are like giant bubbles floating way up high in the sky. They're made of tiny, tiny water droplets or ice crystals. These droplets are so light they can float around up there. Think of it like really, really small bubbles that don't pop easily. The Sun heats the ground, and the warm, wet air rises. As it goes higher, it cools down, and the water vapor in the air turns into those tiny droplets, forming a cloud.

Fog is basically a cloud that's hugging the ground! It's the same tiny water droplets or ice crystals, but instead of being high up, they're right here where we are.

Why is it on the ground? Usually, it's because the ground has cooled down a lot, especially at night. This cools the air near the ground, and if the air has enough moisture, the water vapor turns into tiny droplets, creating fog.

• Think of it like this:

So, both fog and clouds are made of the same stuff - tiny water droplets or ice crystals. The only difference is their location. Clouds are high up, and fog is on the ground! If you were in an airplane flying through a cloud, you'd basically be flying through* fog.