all kinds
Chaps provide protection from the rain, cold, road and bugs. They are not as warm as some manmade materials, and don't provide as good a weather protection from the elements. You can layer up, wear a rainsuit and longjohns, and be fairly warm if your boots are good and you stay dry. However, in a heavy rainstorm, you will be wringing out your chaps.
Manmade fabric jackets and pants offer more weather protection and more protection from crashes with their padding at the knees, hips, etc. I guess it depends on your needs. I have both, plus some padded summer jeans made of fabric that lets the air through. You can wear shorts under them and I think they are cooler than a regular pair of jeans. We also bought some mesh chaps (mesh in back, protective cloth with padding in front). All are expensive but my husband and I've been riding a long time so have amassed a lot of gear. When we used to ride at 40 degrees, I found that manmade fabric pants with liners kept me warm. Now we live where it is rarely 40 degrees, so I don't get much use out of the warmest clothing. I rarely see people with cold weather gear here, and even jackets are optional. So, take a look at your climate and when and where you ride, and start with what makes the most sense for you.
Having grown up in the era of Easy Rider, I've got to say I like the look of chaps the best.