Pre-warp inhabitants of Drema IV, whose world was saved after a young girl made radio contact with Data.
The Dremans are a pre-warp humanoid people living on Drema IV, a planet being torn apart by unstable dilithium formations deep in its crust. A young Dreman girl named Sarjenka sent radio signals into space, and Data answered her calls, striking up a friendship that broke the Prime Directive.
When Picard learned of her plight he chose to intervene, and Wesley Crusher's geological team found a way to stabilize the planet. Data brought Sarjenka aboard, after which Pulaski erased her memories of the encounter to protect her culture. The story is told in the episode Pen Pals.