The gameplay consists of walking between scenes and having dialogues with several different NPC's. There is a jump button, but vertical movement is useless as the levels are flat (with occasional slopes). The game is split into chapters, which starts and ends in front of the girl's journal in her bedroom. When the option to end a chapter has opened, journal pages will appear out of thin air and flutter in the direction of her bedroom to signify it.
The story is narrated in the first-person by a girl's journal writing, which she has just restarted as she finds her journal completely empty and does not appear to know why. She is an unreliable narrator, sometimes obscuring parts of the dialogue or failing to mention details until later on. More of the journal is filled in as you progress through the story, slightly depending on the choices you make, and these journal entries are voice narrated. Every day usually revolves around one big event, with a couple other optional side-stories along the way. The story revolves around her, her parents, schoolmates, and a few other townsfolk she knows. In between chapters, there are seemingly unrelated short stories that are narrated by another person, all of them revolving around a carnival.
Most of the game is set on a hand-drawn two-dimensional world with faceless characters on a journal book. The pages flip around as you move through the scenes. The book itself is actually in a 3D room. During the chapter breaks, the camera turns from the book towards a small puppet stage, on which the short stories are told with shadow puppetry.
According to the project lead Richard Perrin, he has been trying to work on it since the start of 2007. The on-and-off project ended up being shelved, as he proceeded to make Kairo instead. Perrin's father, Michael Perrin, passed away by the end of Kairo's development in 2012. He decided to turn his focus onto Journal in an effort to channel and share his feelings from that experience.
Journal was released for the Linux, Mac, and PC on February 17, 2014.