Almost all home theaters and business organization depend on UHP lamp. These are lamps that use mercury. In projector you will see them called UPH (ultra high pressure), or any of a half dozen plus acronyms. Trying to tell them apart by the different names, is mostly a waste of time. UHP, UHM, NSH, UHE, etc, are the same thing, in almost all cases

Another type of lamp are very high end, and extremely bright projectors, and its totally different. They are Zenon lamps. Comparatively Zenon lamps have a better colour range that mercury lamp (UHP). They are expensive and have very a shorter life when compared to UHP lamps. They tend to start at over $1000, and typically have a lamp life of 500 to 1500 hours compared to UHP lamps good for 1500 to 5000 hours. They also are usually only found on projectors that sell for more than $10,000