Digital Meat covers everything you want to know about C4D’s Texture Tag.
Digital Meat’s Samuel Winter tutorial covers all the stuff you find under Cinema 4D’s Texture Tag. The tag holds quite a few things under it, and Samuel runs through each of their functions.
One of the things possible within the tag is using it to create an easy double-sided surface. Within C4D’s texture tag lies a setting for choosing sides. If you place two materials on one object, you can choose which side of the object will show which textures. You can select either front, back, or both from the list.