Prose is a form of language that has no formal metrical structure.

A poetry verse from "Stopping By Woods On A Snowy Evening" by Robert Frost:

“The woods are lovely, dark and deep.
But I have promises to keep,
And miles to go before I sleep,
And miles to go before I sleep.”

Written in prose form:

“The woods look lovely against the setting darkness and as I gaze into the mysterious depths of the forest, I feel like lingering here longer.  However, I have pending appointments to keep and much distance to cover before I settle in for the night or else I will be late for all of them.”

Common Types of Prose:

Nonfictional Prose
Fictional Prose
Heroic Prose
Prose Poetry