A songwriter is someone who writes the lyrics to songs, the musical composition (chords) or melody to songs, or both. That is to say, a songwriter is a lyricist, a composer, or both. The word "songwriter" is however more commonly used to describe one who writes popular songs than to describe a writer of art songs.
Most art songwriting is written for somebody other than the composer to perform, although it is known that Franz Schubert often sang his own songs at private parties. In fact most popular songwriters of today enjoy having their work recorded by a variety of artists and hearing different renditions.
Many modern rock and roll bands have one or two songwriters, usually members of the band. Then there are songwriters like Bob Dylan, Bruce Springsteen, Billy Joel, John Lennon, Sir Paul McCartney, Prince, Trent Reznor and others that write songs then record them playing their own instruments or all the instruments using a process called overdubbing (see multi-track recording). The advantage to being able to play many instruments and operate a studio is that one can write the music first then weave the words into the tune, experimenting on the way. Still, many songs or foundations of songs are written with simply the songwriter and one instrument. The guitar and piano are the most popular instruments to use for songwriting because they have chordal as well as melodic capabilities. There are no rules, although commercial writers speak of hooks and such required to fit into radio formats, but in the 60s and 70s writers broke new ground and forced the radio to make room for them.
Many songwriters also serve as their own music publishers, while others have outside publishers. Songs in country music are often written by staff writers; songwriters directly employed by music publishers. Legally, songs may only be copied or performed publicly by permission of the authors. The legal power to grant these permissions may be bought, sold or otherwise transferred. This is governed by copyright law. Songwriting and publishing royalties can be a substantial source of income, particularly if a song becomes a hit record.
Songwriters in the popular music genre often also work as record producers, commonly using the professional title Producer-songwriter.
The old apprenticeship approach to learning how to write songs is being supplemented by some universities. It is possible to learn how to write songs. For instance, Bangor University has a degree course, English with Songwriting, which teaches the composition of songs by showing how the metaphorical and rhythmical structures of language are combined with music, in history, theory, and practice. A knowledge of modern music technology and business skills are necessary to make a career in songwriting.