Danny Greer of Premiumbeat.com
has put up a tutorial on the types of lighting stands available and when to use what:
The most common light stand is the C-stand, known for it’s 3 legs of varied heights. The height variation in the legs allows you to nest C-Stands very close to one another, without sacrificing stability. Their heavy, sturdy form makes them ideal for supporting large lighting instruments (a must have on any big film set).
Unlike C-stands, lightweight light stands are much more portable and inexpensive. They’re great for one man band shooters and small crews, but can’t handle heavy weight loads. Other types of light stands include, boom stands, short stands and uni stands. In this video tutorial we touch on each.