Rap is one of the biggest selling music genres today, and many rap artists also consider themselves modern day poets, as do their fans. Whether you prefer poetry over rap or the other way around, there are definitely similarities and differences between both art forms. The main difference is the music.
In poetry, a combination of words will create a rhythm such as iambic pentameter. With this type of phrasing, the first word is an unaccented syllable followed by an accented syllable with a total of 10 syllables per line. There is a rhythm to the phrasing of poetry and rapping. The difference is that the rhythm of rap works in conjunction to the beat of the music, so although the phrasing can be different, both retain a certain type of rhythm and flow of words.
Although rhyming isn't always present in rap or poetry, it certainly is common. In some poetry, the words at the end of two consecutive lines will rhyme, or the words at the end of the second and fourth lines. However, some artists will make a variation of rhymes throughout the poem. Rap will also rhyme, but the beats of the music will sometimes dictate the phrasing as well as the placement of the rhyming words.
With poets and rappers, one of the biggest similarities is their desire to convey a message. The content may differ, but the need to evoke an emotional response is the same. It's typically driven by their view of the world or society and wanting to state their point of view. There is often the use of metaphors within poetry and rap to convey their message and some is written that allows readers or listeners to make their own interpretation.
The most obvious difference in these two artistic styles is that rap is words put to music and poetry is not. Also, a big consideration in rap music are the beats and the groove. In poetry, there is nothing to consider but the words and perhaps the rhythm and rhyme. However, in rap the importance of the beats can sometimes overshadow the importance of lyrics. Rappers are also sometimes concerned with whether or not people can dance to the song. Chances are, you won't find many poets that are concerned with whether or not their poems will inspire someone to dance while reading them.