Telepathy

Telepathy was a psionic mental ability that enabled one intelligent creature to send and receive thoughts to another intelligent creature and communicate without words or a shared language. A creature must know a language to use telepathy.

The use of magic was a common way to use telepathy.

Some creatures possessed telepathy as a supernatural ability. Some intelligent magic items could also communicate using telepathy.

Mental Discipline
Telepathy was also a mental discipline or psionic sub-class. Any psion who focused on this discipline gained experience and power dealing with psionic messages and control of other beings.