What's in a name? That which we call a rose by any other name would smell as sweet.
With these words, Juliet suggests the name of a thing does not matter, only what that thing is. She did have a motive for thinking this, of course, as it was Romeo’s family name, Montague, that posed such a barrier to their love.
No matter what they were named, William Shakespeare’s plays would still be great works of art, so it may not matter what we call them. Generally though, Shakespeare wrote three types of plays: Tragedy, Comedy, and History. These names help us understand the archetypes of a play and better analyze its events. After all, The Comedy of Romeo and Juliet would be a very different play from The Tragedy of Romeo and Juliet. Perhaps it would be a farce about two star-crossed lovers, doomed to suffer humorous mistakes of identity and bumbling servants. It wouldn’t be the story of woe we are all so familiar with.