Conference Room Projectors
Conference Room Projectors are usually installed, and for showing to larger audience sizes (100+ people). The quality you would expect is crystal clear, so try and get WUXGA resolution and if you can go for a Laser technology as they are out of the world, very quiet and can run for hours without any hitches.
Auditorium projectors need to be robust enough to run under challenging conditions, link to my sources and be able to be intergrated into control systems. Often with lens options so they can be placed in various positions, multiple inputs and sometimes dual lamp systems so they never fail.