The World Book Encyclopedia says that "Poetry is a type of literature in which the sound and meaning of language are combined to create ideas and feelings. Poetry began in prehistoric times. Early peoples used poetic language with accompanying music in songs, prayers, and magic spells. The patterns of rhyme and rhythm helped people remember and so preserve oral poetry from generation to generation. After the development of writing, poetry gradually became an important written art.

The three main kinds of poetry are (1) lyric, (2) narrative, and (3) dramatic.

I. Lyric poetry is by far the most common type of poetry. The word lyric comes from lyre, a harplike instrument played by ancient Greek poets during recitals of their shorter poems. Today, lyric poetry means any short poem.
The haiku, a Japanese form, is one of the shortest types of lyric poetry.
The ode is a serious, elaborate lyric full of high praise and noble feeling.

The elegy, another common lyric, is a meditation on life and death. Many elegies mourn the death of a famous person or a close friend.

2. Narrative poetry tells stories. There are two chief kinds of narrative poems: (1) epics and (2) ballads.
Epics are long poems. Most epics describe the deeds of heroes in battle or conflicts between human beings and natural and divine forces. Many other epics tell of the origin or history of a people. Epics are probably the oldest surviving form of poetry.

Ballads tell shorter stories about a particular person. For example, many ballads in English literature describe the adventures of Robin Hood, a legendary outlaw who stole from rich people and gave to the poor. Some ballads date from the 1300's.

3. Dramatic poetry like narrative poetry tells stories. But in dramatic poetry, the poet lets one or more of the story's characters act out the story. Many plays are written as dramatic poetry. The difference between drama and dramatic poetry is a matter of degree. If the dialogue of a play rhymes, has repeating rhythms, or features other distinct poetic elements, the play is considered to be dramatic poetry. The English playwright William Shakespeare is the most famous dramatic poet.
In the dramatic monologue, the story is told in the words of only one character. Robert Browning, an English poet of the 1800's, wrote many poems in this style.

The Elements of Poetry
What first attacts people of poetry is the imagery and sounds of the poet's words.
Rhythm and meter
The word rhythm comes from the Greek word rhein, which means to flow. Rhythm fills the world with repetition and flow, from the beat of our hearts to the rise and fall of ocean tides.
Rhythm in poetry means the flow of sound produced by language. In many poems, we can sense something repeating in the rhythm. This pattern of rhythm in a poem is called meter. Meter gives form to what we hear in a poem by telling us what to expect the flow of language to do from line to line. However, the actual rhythm of any line may not follow the meter exactly. In certain poems, the rhythm varies so much from the meter that the sense of meter is almost lost. The poet's decision to follow the meter closely or to vary from it greatly depends on the particular effects the poet wants to create. The poet may also decide to use no meter at all. Much modern poetry has no meter.
Meter varies according to the sounds of the language in which a poem is written. For example, Cheyenne, an American Indian language, has whispered syllables as well as spoken ones. The meters of Cheyenne poetry reflect this characteristic. The ancient Greeks based their meters on the long and short vowels in their words.
In poetry written in English, meters are based on syllables and on stress (the vocal emphasis given to a syllable). Poets who work in English use three chief types of meters: (1) syllabic, (2) stress, and (3) foot-verse.
Syllabic meters
are based on the number of syllables in a line. The most common syllabic meters are continuous syllabics and stanzaic syllabics.
In continuous syllabics, the poet uses the same number of syllables in each line of the poem. In stanzaic syllabics, the number of syllables in each line of the first stanza is repeated in the corresponding lines of all other stanzas.

Stress meters
are based on the number of stressed syllables in a line. The stress meters most used in the tradition of poetry in English are the Folk Meters. One widely used Folk Meter is Long Measure, which has a pattern of four beats per line.

Foot-verse meters
involve both the number of syllables and the position of the stressed syllables. These combinations form feet. Poets have created many types of foot-verse meters. The most widely used type by far is iambic pentameter, a line consisting of five iambs. An iamb is a two-syllable foot in which the second syllable receives more stress than the first syllable. For example, the words indeed, between, and mistake form iambs.
In many cases, the pattern of stresses in iambic pentameter is harder to hear than in stress meters. In a line of stress meter, we easily recognize the pattern of heavy stresses. In a line of iambic pentameter, however, we must consider all the syllables and compare the stresses of the two syllables that make up each foot to identify the pattern.
If a poem is said to be written in iambic pentameter, the reader can expect each line of the poem to consist of five iambs. In some poems, the rhythm of the lines fulfills that expectation, as it does in these final two lines from "Composed Upon Westminster Bridge, September 3, 1802" by the English poet William Wordsworth:Dear God! the very houses seem asleep;
And all that mighty heart is lying still!
The syllable that has less stress in each foot is marked with a breve. The syllable with greater stress is marked with an accent. The feet are separated by vertical lines called foot boundaries. Marking poetry in this way to find its metrical pattern is called scanning.

Sounds
Poets often use the sounds of words to create effects in their poems. The most common method is to use words that rhyme. If the words at the ends of two or more lines of a poem rhyme, the poem has a rhyme scheme.

Imagery
refers to the sensations that language creates in the mind. These sensations, or images, are often thought of as being like pictures. But images are not limited to visual sensations.
Poets also create images by comparing things that ordinarily have little in common.

Forms
Poets give form to their verse in various ways. The most common means of creating poetic form is rhyme. Some rhyme schemes have been used so often that they have become standard verse forms. One such form is the sonnet. The Italian sonnet, also called the Petrarchan sonnet, consists of an octave (eight-line stanza) followed by a sestet (six-line stanza). The rhyme scheme of the octave is abbaabba. The rhyme scheme of the sestet varies but often is cdecde or cdcdcd. The English sonnet, also called the Shakespearean sonnet, has a rhyme scheme of abab cdcd efef gg. Shakespeare used this form in his sonnets.

A poem's meter also may determine its form. For example, blank verse consists of unrhymed lines of iambic pentameter. The English poet John Milton wrote the great epic Paradise Lost (1667) in blank verse.
Much poetry, especially that written in the 1900's, has no rhyme scheme and no meter. Such poetry is often called free verse."