Good topic, John.
Here are two online resources that give reasonable examples and descriptions of the basic differences between a poem and a lyric.
http://www.songlyric...lyricorpoem.htm
http://andreastolpe....rics-or-poetry/
In another life, my focus was on short stories and poetry. When I made the transition to lyrics, I found I needed to take certain things into account. Below are just a few examples (bearing also in mind that the selected genre will play a role in determining the appearance and content of a lyric). DISCLAIMER: Others here may have experienced things differently.
- The story needs to be expressed clearly; unlike with poetry, the listener doesn't have the luxury of time to stop and try to work out what a particular line means. The story should be coherent, consistent, and progress in a logical manner. Human beings are hard-wired to try to make sense of things.
- The words need to be understood by the average listener. This does not mean 'dumbing down' lyrics; it means selecting the vocabulary most likely to make sense to the listener in the shortest time. Here, genre will play a role. For instance, a prog-rock/New Age lyric will be quite different from a pop-rock or country lyric.
- Structure is necessary so that the composer/vocalist can build the music around it; the listener will be waiting for certain kinds of repetitions. I realised that I needed to learn the functions of various sections of a lyric: rhyming, scansion, verse, chorus, bridge, outro, intro, and so on. I spent time studying well-known lyrics to determine how the lyrics (and music) achieved their particular impact.
- Many lyricists (like myself) don't play a musical instrument. Hence, it's particularly important that lyrics have an inherent flow and consistent scansion/metering so that the lyrics will "sing off the page" and appeal to the musician/vocalist who may be asked to provide the bedtrack and melody.
- Certain 'rules' or guidelines are imposed on lyrics so that the song will have maximum impact in a short period of time. These guidelines in NO way stifle creativity: on the contrary, they push lyricists to be even more creative, to think outside the box, so that their work will be fresh, original, and compelling even within the parameters of 'rules/guidelines'. And once a lyricist learns the rules, and has become adept at writing, she/he can bend or ignore them. But first - as with any craft or skill - it's necessary to learn them, because they're the key to what will capture and hold listener interest. Of course, if you're writing simply for yourself/family/friends, and with no thought of reaching a wider audience, you can write any way you want to.
- The lyric - again depending on the genre - needs to fit within a certain time frame. In the beginning, the hardest thing was to reduce the story from, say, 15 verses to 6 at the most (and including a chorus and perhaps a lyrical bridge). With a lyric, I couldn't indulge in rambling on the way I might have in an abstract poem. I needed to hook the listener quickly, make my point, entice (I hoped) the listener to care, and then bow out.
There were other things as well, but in summary, it's been about learning a certain kind of discipline. Transitioning from poetry to lyrics doesn't mean forfeiting one's command of the language, creativity, feel for words, or love of metaphor, similes, and other poetic devices, and so on. On the contrary. These are essential for writing effective lyrics in any genre. It means knowing how to apply these most effectively in a form that will appeal to a listener rather than just a reader.
I hope the above ramble is useful.
Donna