A song is a group of words or melody that expresses an idea or emotion. It may be accompanied by music, such as a guitar or piano, or it may be without instruments, as in the case of a cappella singing. The term also encompasses a broad range of musical styles, including classical, folk and popular music.
A song may be for a single singer, a lead singer supported by backup singers, a duet, trio or even a larger ensemble such as a choir or an opera. The word is not generally used for large classical vocal forms such as aria and recitative, which are referred to by different terms such as solo and choral song respectively.
Before you start writing the lyrics to your song it is helpful to have a clear idea of what you want to communicate from the very beginning. This helps you to avoid getting stuck halfway through your song and wondering what on earth you were thinking when you first wrote it.
Having a blueprint of the song before you write it also ensures that each element will have a job to do and a place in the overall song structure. You will find that the lyrical ideas will help guide you to the best bassline or kick that it needs, for example, and the melodies will tell you where they need a little embellishment.