just got back into PS and when reading through some tutorials on here theres a lot of mention about C4D's and i dont know what they are are they brushes made from 3d renders?
Everyone pretty much said it, they can be used in GFX in many ways. You can use blending modes to blend thme in better and do lots of things. They are made using 3D programs such as Cinema 4D.
C4D's are abstract 3 demensional renders made in Cinema 4D. Hence their name "C4D" I usually just copy and paste them into the background and play around a bit, but theres other stuff you can do too ^_^;