The document summarizes three literary collections:
1) Collection 11 discusses symbolism and imagism in early 20th century American poetry, which rebelled against tradition in form and content. Imagism emphasized precise imagery over decoration.
2) Collection 12 examines modernism in American fiction after WWI, which rejected sentimentality in favor of realism. Writers like Hemingway, Fitzgerald, and Faulkner experimented with style to capture social fragmentation.
3) Collection 13 focuses on the Harlem Renaissance, where black talent in various arts flourished in Harlem in the 1920s. Jazz influenced mainstream culture and authors drew on African American dialects and folk traditions.