Empaths are often very sensitive people, and may 'feel' the emotions they perceive rather than merely detecting them. Empathy is something akin to telepathy, but telepaths generally read thoughts rather than feelings.
For some systems, such as the Eodean, empathy and telepathy are closely related or indistinguishable. Some worlds, such as Shade, may not have real empathy powers at all, but people still believe in it!