Think of tags as like a book index where you find words and which pages they are on, the same principle applies here. Although it's taken a stage further so it might not be the word, but the subject, so for example if you're looking for things to do with fractal gradients for example. A tag may bring back posts with gradient files, as well as posts that discuss gradients, or tutorials about them.

Curling Julia OScope AA BS

Curling Julia OScope AA BS

Based on a flame by Amorina Ashton using Curl3D, julia3Dz and oscilloscope with a random variation. Created with permission