from the Yume.Wiki:
"Yume Nikki (ゆめにっき, pronounced /jɯmeꜜ nikki/) is a 32-Bit freeware game created by KIKIYAMA, a mysterious Japanese game designer. The game was made using RPG Maker 2003, and is regarded as one of the most original applications of the software, as well as the start of a possible new genre of games. It was initially released on June 26, 2004 (under version 0.00), and received numerous updates until October 1, 2007, when version 0.10 was released.
"Yume Nikki" means "Dream Diary" in Japanese (and thus can be written as 夢日記, although the title is normally in hiragana), and the game follows a girl named Madotsuki as she dreams. The goal is to seek out and acquire all 24 "effects". The game otherwise has no actual plot or dialogue, and nearly the entire game is left up to speculation."