I like to think of a craft knife as an all-in-one cutting tool. That’s because there are so many types of interchangeable blades available (photo at below).
You can use it with a standard blade as a marking knife or switch to a thicker blade for carving and cleaning out the waste of a hinge mortise. And like a utility knife, the blades can be thrown out when they get dull. Just keep in mind that the blades are beveled on both faces.
The knife handles and blades can be purchased individually or in a set (as shown). You can find them at most craft and hobby stores.