* History: Shakespeare's plays often draw on historical events and figures. For example, his play Julius Caesar is based on the assassination of the Roman emperor Julius Caesar, and his play Macbeth is based on the life of the Scottish king Macbeth.
* Nature: Shakespeare's plays are full of references to nature, and he often uses nature as a metaphor for human emotions and experiences. For example, in his play The Tempest, he uses a storm to represent the turmoil in the characters' lives.
* Travel: Shakespeare traveled to Italy and France, and his experiences in these countries influenced his plays. For example, his play The Merchant of Venice is set in Venice, Italy, and his play Hamlet contains references to the French court.
* Human nature: Shakespeare was deeply interested in human nature, and his plays explore a wide range of human emotions and experiences. He wrote about love, loss, ambition, greed, and betrayal.