lignite coal is a soft, low btu (around 8,000btu/lb) coal with a "peaty" or "clayish" consistancy. it tends not to form clinkers easily partly because of the lower temps at which it burns; it also will not form conglomerations of sticky coke. in my opinion after having tried out some it is the best coal i've ever burned aside from the lower heat content. if i could get a truckload to my home economically i would in a heartbeat. It is not a smokeless coal either, and tends to burn somewhat smokey under most conditions, although not unlike wood. I would say that it is probably the "easiest" coal to burn and is far more forgiving than bituminous, and anthricite as well, but for different reasons.
btw, the admin beat me to the response by a few minuites i realize on edit, however, i would say it is an excellent home heating fuel, and will burn very nicely in an open fireplace as well.