Terl's World is a fictional planet featured in the science fiction novel "Battlefield Earth" by L. Ron Hubbard. It is depicted as a harsh environment dominated by the alien race known as the Psychlos. The planet's landscape includes vast deserts, toxic air, and dangerous wildlife, making it a challenging place for survival. The story follows the struggles of humans who are enslaved by the Psychlos and their efforts to reclaim their freedom. The protagonist, Jonnie Goodboy Tyler, embarks on a journey to unite the remaining human population and fight against their alien oppressors, showcasing themes of resilience and hope.