Feet are the repeating metrical units that make up a line of verse. Each foot is built from a pattern of stressed and unstressed syllables, such as an iamb or trochee, and the number and arrangement of feet help shape a poem's rhythm.
Poets and readers often count feet to describe meter, as in two feet, five feet, or six feet per line.
Example
The soft rain fell / on window glass
and woke the / sleeping grass.