According to inventor Philipp Hübner, Loopy was inspired by two puzzles: one is Takegaki; the other is an old puzzle involving the construction of a railway track in a matrix.
Puzzles can be any size, but a typical puzzle is contained in a 10x10 grid. The grid contains an apparently random arrangement of bits of loop. The objective is to join all segments to form a single loop through all cells.
Philipp's aim was to devise a logical puzzle without numbers so simple that it could be understood by a child. The puzzle can be challenging but, even so, it is said to be particularly popular with children.