A collection of short stories by the grandfather of modern horror. I typically don't like horror at all, but Lovecraft is an unusual case. First, the terror in his stories is typically achieved with creepy subtlety - reminiscent in many ways of Poe - rather than outright grossness or gore, like that found in so much modern horror. Second, he had a unique vision (Wikipedia calls it "cosmic pessimism", which nails it perfectly) of the universe which pervades his works.

Lovecraft created the Cthulu mythos. He wrote The Necronomicon, a sort of bible for this mythos, and released it as if it were a nonfiction work.

He was also a contemporary of Robert E. Howard, writing pulp fiction stories of similar length for the scifi mags of the time, in the first few decades of the 20th century. All in all a fascinating individual with a fascinating body of work.