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.
In this tutorial, Brad walks us through the new Z-buffer facility on JWildfire 7.20. This allows the creation of depth maps, which, when loaded with the original image will create wonderful 3D images on Facebook, and some others.
Variations that generate meshes, three dimensional shapes made from connected triangles. These are all blur variations that ignore their inputs. They are most useful for solid renders, though they work for normal flames as well.