Each entry in the International Music Score Library Project, also known as the Petrucci Music Library, contains a blurb about the music, its composer, the breakdown of movements, background information and the estimated running time of a full performance. The homepage displays up-to-the-minute links to newly added scores and recordings.
Site visitors can search for sheet music or recordings with an IMSLP number, the title of a work, the composer's name, the time period or instrumentation. The website also features a means to browse recordings by composer or performer.
Musical scores are usually available as a PDF or as either a digital reprint or a digital scan of a commercially published score. Members of IMSLP upload personal copies of scores, which may encompass song cycles in different keys, piano/vocal scores of operas, full scores of operas, symphonies and chamber music.
Individual parts of larger works are occasionally available as well. While the IMSLP collection leans heavily toward pre-20th century classical music, some public domain 19th- and 20th-century music is also available, such as the songs and piano sonatas of Charles Ives and the later symphonic works of Igor Stravinsky.
The International Music Score Library Project is a nonprofit, member-driven, digital library that offers free access to public domain musical scores and recordings. As of May 2015, the collection includes approximately 300,000 scores and 35,000 recordings.