Fables are short literary works that convey a universal moral truth, and Aesop is a former slave in ancient Greece whois said to have written many of them. Many stories, such as "The Ant and the Grasshopper" are very familiar to most readers.
There are scores of fables attributed to Aesop. To learn more, explore Aesop's Fables Online Collection. With each one you'll find the corresponding moral that the story intends to teach. Fairy tales and fables by other authors are also available.