The First Folio is a collection of William Shakespeare's plays published in 1623. It is considered one of the most important books in English literature, as it contains 36 of his works, including famous plays like Hamlet and Macbeth. The First Folio was compiled by two of Shakespeare's friends, John Heminges and Henry Condell, to preserve his writings after his death. Before the First Folio, many of Shakespeare's plays were published in smaller, less reliable editions. The First Folio helped standardize his works and ensured that they would be read and performed for generations. Today, it is highly valued by collectors and scholars alike.