Here's why:

* Colloids are mixtures where one substance (the dispersed phase) is evenly distributed throughout another substance (the dispersing medium).

* The dispersed particles are larger than molecules but smaller than what you can see with the naked eye. This means they are too small to settle out of the mixture due to gravity.

* Examples of colloids include milk (fat droplets in water), fog (water droplets in air), and paint (pigment particles in a liquid).

Let me know if you'd like more details about colloids!