The term “iambic pentameter” can seem intimidating to someone unfamiliar with poetry. Anyone with a passing Shakespeare familiarity will likely associate the term with the Bard’s work, but may not have a clue what it really means or what purpose it has served to other writers like Geoffrey Chaucer and Alexander Pope.
William Shakespeare (40049)
Iambic pentameter is a meter of poetry, utilized by a variety of poets, but made most famous by William Shakespeare. An “iamb” is a “foot” of poetry that consists of on unstressed syllable followed by a stressed syllable. The word “about” is a good example of an iamb. Try saying “about” with the stress on the first syllable - sounds wrong, doesn’t it? Some words, like about, are natural iambs, but many are not, so a poet who writes in iambs often needs to be clever with the structure of his lines, or take some poetic license (pun intended) with the pronunciation of certain words.

Pentameter just refers to how many “feet” are in a particular line of poetry. A poetic “foot” is just a group of particular number of syllables. An iamb always consists of two syllables, so a poem written in iambic pentameter has five iambic feet (for a total of ten syllables) to one line.
Romeo and Juliet (39097)
The question many people might ask now is “so what?” Why should anyone care? Why would anyone write that way? What happens when a poet adheres to such strict guidelines when he writes? This happens: “But soft! What light through yonder window breaks? It is the East, and Juliet is the sun.” Those words were uttered by one Romeo Montague, and while it may not be the most well-known of the Romeo and Juliet quotes, it’s arguably amongst the most beautiful. The second line (“It is the East, and Juliet is the sun.”) is an example of Shakespeare taking some liberties with his chosen form, but the first line (“But soft! What light through yonder window breaks?”) is textbook iambic pentameter and a great introduction to Romeo’s declaration of his intense, if slightly impulsive, love for Juliet.

Hamlet (25495)
Shakespeare also veered from perfect iambic pentameter in this famous line from Hamlet, “To be or not to be: that is the question.” This line actually has eleven syllables (as opposed to the standard ten), but Shakespeare enthusiasts and casual fans alike could probably agree that they wouldn’t want it any other way.

Poetry written in a specific form can really inform the content of a poem. Forms can be tricky, as they force writers to be creative with their diction and word choice to make the meter and rhymes work, but they can also help the writer create his poem by giving him a frame upon which to build; almost a literary paint-by-numbers (though of course it helps to be as talented as Shakespeare was to begin with; not everyone who tries to write in iambic pentameter is going to be able to produce Romeo and Juliet).