What are the five types of titles that should be underlined?

The five main types of titles that should be underlined are:

1) Books: The titles of complete books, including novels, biographies, and textbooks.

2) Magazines: The titles of magazines and journals.

3) Newspapers: The titles of newspapers.

4) Plays: The titles of plays and musicals.

5) Long Poems: The titles of long poems, such as epics or narrative poems.