Shakespeare became a shareholding member of The Lord Chamberlain's Men in 1599. Scholars estimate that until about 1603 the average payment for a play was £6 (six pounds); by 1613 the price had risen to £10 or £12. In addition to his fee, the playwright was given all the receipts (minus company expenses) at the second performance (but remember, if the show was bad, there may not be a second performance). Once these fees were paid, however, the play was considered property of the troupe. Printers often pirated more popular works, and troupes sometimes sold publication rights during times of financial stress. Such publishing practices, combined with the fact playwrights, including Shakespeare, didn't write with the intention of preserving their plays but with the goal of making money, makes it difficult for scholars to pinpoint definitive texts. In Shakespeare's case, only about half of his plays were published during his lifetime.
In fact, it wasn't until 1623, seven years after Shakespeare's death in 1616, that all his plays were assembled into one volume. This collection, referred to as The First Folio (because it was printed in folio format, the largest, most expensive, and most prestigious kind of book), included previously published plays as well as plays never before published. Some of the works in The First Folio can be traced to the author's original version of the text (including blotted lines and revisions), yet some were recreated from prompt books (annotated versions of the play script that contain detailed directions for the action, settings, etc.) or even the memories of the actors themselves (helping to explain some of the inconsistencies found in different editions of the plays).
