The game's framework is centered around discovering the player's "practical intelligence quotient," by completing a test consisting of 100 puzzles. The player controls a white, human-like avatar who can interact with the game world. The puzzles are all logic-based, and include a variety of tasks, from rearranging blocks to avoiding security guards to operating machinery. In most of the levels, an exit must be reached to complete that stage.
After clearing all 100 levels, the player's score is determined based on how long each stage took, among other variables. The player's PQ can be taken online and be compared with other players' scores (a high score table is also available online).
Source: Wikipedia, "PQ: Practical Intelligence Quotient", available under the CC-BY-SA License.