Interactive Fiction (or IF for short) is both a computer game and a book, or rather something in between. You usually take on the role of the main character in a story. The game tells you what happens to the character, and you tell the game how the character should act. This is not always simple, but can make for a very rewarding experience. The game's output is always mainly text based, but there are some games that will also show images and play sounds. You communicate with the game using text as well, but there are indeed a small number of games that complement this with mouse support.Many games have problems for you to solve, also called puzzles. How and when you solve these puzzles may affect how the plot unfolds and even the outcome of the game. There are also games that don't have puzzles, but rely on the story itself being good enough to keep the player's interest. The story can still take multiple paths, depending on the player's choices, but the game isn't meant to be an intellectual challenge as such. The first category of games is sometimes called traditional IF or puzzle-based IF or just text adventures, while the latter is called puzzle-less IF. There are of course games that are a mix of these two, as well as experiments with the genre that don't fit in anywhere yet.