1. The Grapes of Wrath (1939): This Pulitzer Prize-winning novel is a powerful depiction of the Dust Bowl era and the struggles of the Joad family, forced to leave their Oklahoma farm and migrate to California in search of a better life. It's a testament to Steinbeck's social conscience and his ability to capture the human spirit during times of hardship.
2. Of Mice and Men (1937): This novella, often studied in high school, tells the story of George Milton and Lennie Small, two migrant workers who dream of owning their own farm. The novel explores themes of friendship, loneliness, and the harsh realities of life during the Great Depression.
3. East of Eden (1952): This sprawling epic, considered by some to be Steinbeck's magnum opus, spans multiple generations of the Trask family and explores themes of good and evil, love and loss, and the search for meaning in life. It's a complex and deeply moving work that showcases Steinbeck's masterful storytelling abilities.
While these are considered signature works, Steinbeck wrote many other acclaimed novels and short stories. You can find more on his bibliography online.