Short answers, pulled from the story.
A chivalric romance is a type of prose and verse narrative that was popular in the noble courts of high medieval and early modern Europe. These stories featured marvel-filled adventures centered on a knight-errant who goes on a quest, and were distinguished from earlier epics by their emphasis on love, courtly manners, and interwoven plots rather than straightforward military heroism.
The French poet Jean Bodel first described the three cycles in the 12th century in his epic the "Song of the Saxons." He named them the Matter of Rome, the Matter of France, and the Matter of Britain, and medieval authors explicitly described these three as comprising all romances.
Chrétien de Troyes introduced courtly love to the romance genre, combining it with the Matter of Britain. His work Lancelot, the Knight of the Cart was notable for devoting an unprecedented amount of attention to the psychological aspects of love.
Don Quixote, published in 1605 and 1615, satirized the chivalric romance genre by depicting an elderly gentleman from La Mancha so obsessed with romances that he tries to emulate their heroes. By 1600 many learned readers had come to view romance as trite and childish literature, and Cervantes gave the genre its most famous satirical treatment.
The Swedish work Frithjof's saga, based on the Old Norse Friðþjófs saga ins frœkna, became widely popular after 1825 and was translated twenty-two times into English and twenty times into German. Its influence, along with the broader romance tradition, was considerable on authors including J. R. R. Tolkien, William Morris, and Poul Anderson.
Several of Shakespeare's later comedies, including The Tempest and The Winter's Tale, are sometimes called his romances. The Winter's Tale drew directly from Robert Greene's Pandosto, and As You Like It was sourced from Thomas Lodge's Rosalynde, which was itself based on the medieval romance Gamelyn.