This is a list of musical compositions or pieces of music that have unusual time signatures. "Unusual" is here defined to be any time signature other than simple time signatures with top numerals of 2, 3, or 4 and bottom numerals of 2, 4, or 8, and compound time signatures with top numerals of 6, 9, or 12 and bottom numerals 4, 8, or 16. The conventions of musical notation typically allow for more than one written representation of a particular piece. The chosen time signature largely depends upon musical context, personal taste of the composer or transcriber, and the graphic layout on the written page. Frequently, published editions were written in a specific time signature to visually signify the tempo for slow movements in symphonies, sonatas, and concerti. A perfectly consistent unusual metrical pattern may be notated in a more familiar time signature that does not correspond to it. For example, the Passacaglia from Britten's opera Peter Grimes consists of variations over a recurring bass line eleven beats in length but is notated in ordinary 44 time, with each variation lasting 2+3⁄4 bars, and therefore commencing each time one crotchet earlier in the bar than the preceding one.