Pentameter is a poetic meter, which means it refers to the pattern of stressed and unstressed syllables in a line of verse. In English poetry, pentameter typically follows one of two patterns: iambic or anapestic. Iambic pentameter has five pairs of unstressed and stressed syllables per line, while anapestic pentameter has five sets of two unstressed syllables followed by a single stressed syllable. Pentameter is often associated with the rhythmic structure of Shakespeare's plays and sonnets, as well as many other works in English literature.