Rhythm is often the most commonly associated and vital element of sound in a poem. Rhythm is arranged in meter. Classical, Early European, Eastern and Modern poets all used different forms of meter to determine the sound of their writing. There are five basic rhythms in English poetry with varying stressed and unstressed syllables. These meters are called iambs, trochees, anapests, spondees and dactyls; with each unit of rhythm being a "foot" of poetry.
Rhyme as a device in poetry is often found in ballads, sonnets and couplets; keeping in mind that most traditional poetry avoids rhyming and has a looser cadence. Rhyming has been used extensively by Europeans since the 14th Century; while in Greek and Latin poetry it was rare to find the use of rhyme as a device for sound. A rhyme in a poem is used to appeal to the reader's senses. By definition, rhyme in a poem is two words with similar-sounding ending syllables placed to echo one another.
"Sally sells seashells by the seashore. The shells Sally sells are surely from the sea," is an example of alliteration. Alliteration pairs identical or similar sounding consonants in a poem. The sound in alliteration does not always have to be presented by the same letter; the sound should however be similar. Using alliteration too heavily in a poem can give it a comedic effect. A poet who is not trying to be funny should find a balance within his use of alliteration to even the sound.
Onomatopoeia is often used in free verse poetry. Using varied patterns, placing emphasis and illustration on words that sound like they mean can bring sound to a poem. Onomatopoeia is using a word as suggestion or imitation of itself such as boom, whisper, achoo, and fizz. This works well in poetry because it is made for not only the eye, but the ear. Poetry often relies on sound effects. The use of onomatopoeia in poetry as a device of sound has been reflected through both classical and traditional poems.