A projector lamp is made up of a light bulb inside of a module. The bulb is an advanced piece of technology developed over the last 50 years, providing high brightness, contrast, and is designed to last. There are only 7 companies worldwide manufacturing bulbs, the main one being Philips. The bulb manufacturer's then send the bulbs to the Projector Manufacturers (ie Sony, BenQ, Epson etc...) who put them into a module, creating a "Genuine Lamp".
Projector lamps are a fragile item when powered up and in operation, but are suprisingly durable and quite safe to transport when in their cooled state. They are packed in a protective box and sent via courier to ensure they are treated with care. Additionally we insure our deliveries in case any damage occurs.
With a genuine branded lamp (ie a lamp sourced from the projector brand directly and not from 3rd party manufacturers), you will be putting in the exact same product your projector originally shipped with. You will have the same performance as the projector was intended to have. There is obviously no point spending a fortune on a brilliant projector just to have the image downgraded by a non-genuine lamp. Genuine branded lamps will not void your projectors warranty and are the safest lamp type, meeting all electrical safety regulations that copy lamps may ignore.
Projector brands usually do not sell "bare bulbs", the bulbs are supplied in a module (which together we call a lamp). Some stores may sell 'bare bulbs' however you can almost be certain these are generic bulbs and not from the projector brand. Installing a bulb is significantly more difficult than a lamp, sometimes actually requiring soldering. The risk in damaging the projector is more than often not worth the cost saving.
Unfortuantely the vast majority of online dealers now only sell generic lamps or bulbs, and they sometimes are not overly clear or forthcoming with what the lamp actually is. Generic lamps/bulbs can be cheaper up front but performance is rarely the same as a Genuine Branded Lamp. We usually only recommend using a generic lamp if your projector is very old and you don't mind if the lamp doesn't perform the same.
Generic lamps can sometimes still be advertised as "genuine" by stores. They can sometimes use tricky language can mean different things. We find many generic lamps can be identified by phrases such as "compatible lamp", "genuine lamp in module", original bulb in housing.