A collection of stories, curated by Frederick Pohl who included some minor anecdote or context in the introduction to each story.
These are some well written and excellent stories that contain some pretty unique or different ideas. Not all are scifi or the scifi element is only a backdrop to the story. "The Words of Guru" could be considered horror, about a young boy who gains forbidden knowledge from eldritch beings.
"Mindworm" is about a child who can read minds and finds he can absorb thoughts from others, becoming something of a vampire. But being able to read minds doesn't protect you when you don't know the language.
"Gomez" is from the point of view of a reporter who befriends a young dishwasher from New York whose instinctual grasp of physics gets him drafted into the Army's atomic energy program.
"Little Black Bag" was adapted into a Twilight Zone episode and got a spinoff in "Marching Morons," which has a similar plot to the later movie "Idiocracy" but was better written than that film.
I don't want to speak more of the other stories, risking spoiling the endings for for first time readers.
The book is out of print. If like me, you find a copy in a used book shop, give it a try.