At the time when Shakespeare was writing no playwright ever considered to publish his works. The most succesful plays were published without the author's permission, maybe copied from promptbooks, notes or copy books. Therefore, texts published were often unreliable.

These unreliable works were called "bad quartos" referring to the sheet of paper folded and thus divided into four parts on which they were written. A ‘bad quarto’ of Romeo and Juliet came out in 1597; in 1599 , a ‘good quarto’ of the play came out. This quarto was called good because it was revised and checked from the author or copied from an original manuscript.

In 1623 the first accurate and complete of Shakespeare’s works came out. It was known as the first ‘folio’( consisting of a sheet of paper folded once)

Sometimes happens that we don't know the date of composition of a work but we can find out some informations from other works; some plays are mentioned in the "Stationers' Register", other are documented in some author's works, some of them contain contemporary historical events.The style is also very important to find out the date infact every historical period has his own style .