Shown here is the nematode Caenorhabditis elegans crawling on an agar surface followed by a homemade tracking video microscope. C. elegans is a small (1mm in length), free living worm that is commonly found in the soil. C. elegans moves forward by wiggling sinusoidal waves down its body and changes direction by performing pirouettes, a choreographed sequence of turns and reversals. By studying these patterns of motion we hope to better understand the behavioral biology of C. elegans.