Textures don't have to be limited to color maps. You can create textures to drive almost any channel in your material. A bump map is a grayscale image that acts as a pseudo-height map. It doesn't actually create any extra geometry, all a bump map does is create the illusion of raised or lowered details on the surface of your model. Usually if you have something darker than a 50% gray in your bump map, it'll appear as if it's pushed down into the surface while anything lighter than that will appear to be raised up.
An important thing to keep in mind when you're using bump maps, is that the silhouette of the object will remain unchanged, because as mentioned before the bump maps don't actually create any extra geometry. For that reason, bump maps are really great for adding in smaller details where the silhouette doesn't need to be affected.
You can learn more about creating bump maps in Creature Creation in CINEMA 4D
If you do need your details to affect the silhouette, a displacement map is a very powerful option in your texturing tool belt because it actually does affect the geometry itself. Like a bump map, a displacement map is basically a height map with the primary difference between a bump and displacement being that the displacement actually affects the geometry.
A common workflow for creating displacement maps is to bake them out from a high resolution mesh in a sculpting application like Mudbox or ZBrush. Once you've baked them out from the high resolution mesh, you can apply the displacement to a lower resolution version of the model. This allows you to get some really high quality detail while still keeping the mesh resolution manageable for future steps in the pipeline, like rigging and animation. If you'd like to learn more in-depth about the differences between bump maps, displacement maps and normal maps.
You can learn more about creating displacement maps in Sculpting Integration Concepts in Maya and ZBrush
While displacement and bump maps have their own pros and cons, yet another type of pseudo height map is a normal map. Instead of a grayscale image like a bump map, a normal map is basically a map of what direction your geometry's normals are facing. With this information, the illusion of anything from height to how your model is affected by lighting can be faked.
Generally speaking, normal maps are used a lot in games where real-time rendering can take advantage of how different lighting angles might affect your model's geometry in different ways. If you're thinking there's a lot of similarities between bump, displacement and normal maps you're not alone.
You can learn how to create normal maps in Aging Wood and Metal Textures in Photoshop
In the image above, notice how around the character's eyes the skin appears to be shinier than the area under his chin? That's done with a specular map that tells the 3D program how shiny each area of the model should be.
As another example, a wet piece of plastic will reflect light completely differently than a dry piece of plastic. The color may be the same and it may have the same amount of bumpiness, but you can control how shiny it is with a specular map. For a basic specular map, you can use dark tones to reduce the specularity and lighter tones to create a stronger highlight.
You can create specular maps manually, paint them interactively in programs like Mudbox and MARI or you can start with a color map and adjust the levels or curves to create your final specular map.
You can learn more about creating specular maps in Creating Game Weapons in Maya and Mudbox
Sometimes it'd be nice to combine multiple materials or textures together on a single object. With mask maps, you can do that by using the black and white values of the map to define which texture layer is displayed on which area of your object. While it can vary depending on the program you're using, in most cases white will define areas for the texture to be visible while black will display the other layers.
Using mask maps is a very flexible and non-destructive way to work because it lets you change where the textures appear without actually touching the maps themselves. You can use them to blend textures together or create cut-outs for decals or tattoos.
You can learn more about creating mask maps in the Professional Series: Texturing Military Vehicles in MARI tutorial
When you've got large surfaces to texture, it's often necessary to create the map from just a small texture. For instance, if you need to texture an entire parking lot but you've only got a photo of a small portion of asphalt from your driveway then once that small texture is applied to the large area it'll look distorted.
Instead, what you can do is to repeat, or tile, the smaller texture across the geometry. The catch to this is that tiling can cause visible seams if you're not careful. To avoid this, most texturing programs have tools that let you repeat the edge pixels. By doing this you can create a new image that will tile seamlessly across your entire surface and avoid any visible seams.
You can learn more about tiling textures in Creating Seamless Textures for Games
Now that you've been introduced to many of the industry-standard texture maps, you'll be better prepared in your next texturing project. Most of the maps we've looked at so far can be created in a wide range programs. They can be created manually in a program like Photoshop
or you can interactively create them in programs such as Mudbox
You can dive deeper into texturing by following any of the links for the map you want to learn above. Or, if you'd like to learn more about the different texturing terms, you can do that by following along with the CG101: Texturing
Explore more animation tutorials on Digital-Tutors website
Try the 3dtotal tutorials for more tips on texturing
Grab some textures from the 3dtotal textures library