The Ximegans were a humanoid race that were native to the planet Ximega I. By the 22nd century, the Ximegans had developed advanced communications technology and were experimenting with holographic technology.
It was through the use of advanced holographic technology that had been developed by Prekraft, a scientist, that allowed every member of the Ximega civilization to have the physical and mental patterns to be recorded and made into holograms, and sent off planet in a probe, before a supernova claimed Ximega I and the Ximegans.
Eventually the probe arrived on a habitable planet in Sector 061, and the Ximegan population was reborn on the planet, which they named Ximega II. Led by a holographic Prekraft, the Ximegans built an impressive colony on the surface and built several impressive structures, including a Great Library, which contained all of the historical and instructional texts that had been saved from Ximega I.
Unfortunately, solar storms laid waste to the colony and destroyed all Ximegan and animal life, apart from Prekraft and his wife, Lin, who managed to escape below the surface. When Lin later died from a native virus, Prekraft discovered that the complete consciousness of the Ximegans were destroyed and he couldn't recreate them. Instead of living alone until he died, Prekraft reconfigured his molecular assembler to link directly to his brain and recreate the colony using only his memory. This caused Prekraft great pain, and he was eventually rescued by the crew of the USS Enterprise in 2267, after destroying the colony himself. (TOS comic: "Anything But Alone")