Things you can stick on your sims - skintones, clothing, and more.
Pattern, Wall and Floor Tutorials
Create a Style patterns for use on all manner of items in-game, plus wallpapers and floor coverings.
Object Creation Tutorials
New objects that can be placed in game as furniture or build mode objects and object recolors.
Instructions and help on building the perfect lot in Sims 4.
General Modding Tutorials
Creating gameplay modifications and the like.
Advanced Modding Reference
If you are interested in all the file formats that go to make up the game.