The First Folio of 1623 is the definitive edition of Shakespeare's plays. It is more often than not the closest we can now get to what Shakespeare actually wrote. But the Folio's antiquated typography and cramped layout make it remote and inaccessible to modern eyes.
The Shakespeare Folios, on the other hand, offer easy access directly to the First Folio by presenting the text in modern type but otherwise unchanged. As an additional aid to understanding, readers will find, printed opposite each page of the Folio, the very same passage in a modern edition.