Shakespeare's works contain first-ever recordings of 2,035 English words, including: critical, frugal, excellent, barefaced, assassination, and countless.
Many of Shakespeare's plays are based on others' earlier plays, histories, and poems. This was common practice at that time.
The first definite reference to Shakespeare as a playwright is in a pamphlet by Robert Greene, who wrote, “There is an upstart Crow, beautified with our feathers, that with his Tiger's heart wrapped in a Player's hide, supposes he is as well able to bombast out a blank verse as the best of you: and being an absolute Johannes fac totum, is in his own conceit the only Shake-scene in a country.” “Tiger's heart wrapped in a Player's hide” is an allusion to a line from Henry VI, Part 3.
Shakespeare is listed as an actor on documents from 1592, 1598, 1603, and 1608. It is supposed that he played mostly unassuming parts, such as the ghost in Hamlet, to allow him more time to write.