Otherland is a science fiction tetralogy by American writer Tad Williams, published between 1996 and 2001. The story is set on Earth near the end of the 21st century, probably between 2082 and 2089, in a world where technology has advanced somewhat beyond the present. The most notable advancement is the widespread availability of full-immersion virtual reality installations, which allow people from all walks of life to access an online world, called simply the Net. Tad Williams weaves an intricate plot spanning four thick volumes, and creates a picture of a future society where virtual worlds are fully integrated into everyday life.