Most people recognize Poe by his famous poem, "The Raven". Others may have read one of his more popular dark and creepy tales like, "The Fall of the House of Usher" or "The Tell-tale Heart".
Poe wrote quite a few gothic stories about murder, revenge, torture, the plague, being buried alive, and insanity.
Many modern books and movies have "borrowed" ideas from Poe. Some of Poe's stories were not well accepted in his day because people were just not ready for them- they were too scary.