Just like Windows XP, Mac OS X is extremely camera-friendly. The simple act of connecting a digital camera to its USB cable stirs Mac OS X into actionnamely, it opens iPhoto, Apple's digital-photo shoebox program. See Section 14.14 for a crash course.
If it's a digital video camera you plugged in, Mac OS X opens iMovie instead. Section 14.12 has an overview of this useful video editor.