The Legend of Zelda: The Minish Cap/Characters/Minish

In The Legend of Zelda: The Minish Cap, the Minish (known as Picori for the Hylian) are the thumb-sized people living in Hyrule.

They came from another world, through a portal that only opens every 100 years, and they are the ones hiding items in tall grass, under rocks and so on. They do this to make people happy.