What were John Steinbeck's main writing genres?

Although best known for writing in the fiction genre, the author wrote in other formats as well.

=== === Steinbeck primarily wrote novels, several of which take place in California during the Dust Bowl, and are drearily realistic (like Grapes of Wrath). He also wrote propagandistic novels (like The Moon is Down).

=== === Some of his fiction is in a shorter format, such as The Pearl and Of Mice and Men.

Steinbeck's non-fiction works range from travel writing (Travels With Charlie) to numerous journalistic essays.

He wrote the scripts for some of his own works, such as The Red Pony and The Pearl, and also wrote the story for Hitchcock's Lifeboatand the screenplay for Viva Zapata!