Termina is the name of the world where Link's journey in Majora's Mask takes place. It is discovered by him when he is searching for Navi and chases Skull Kid. It has a different biome in each of the four compass directions as well as an extra area for Romani Ranch. It is in danger of the moon crashing into it, so it is up to Link to keep that from happening.
In the center of Termina lies Clock Town. It is populated by the human race of the series. Around it is Termina Field, which leads to five different areas. North of Clock Town is Snowhead, west is Great Bay, east is Ikana, and south is Woodfall. There is also a ranch to the southwest.