Shakespeare (or whoever he was) wrote a lot of great plays, full of tragedy, comedy, and the human condition. Of course, the human condition is hard to express in writing without a language, and English (or, at least, the English of Shakespeare's day) was rather sparse. There simply wasn't a single word for "lonely" or "generous."
So Shakespeare did what any person in search of the right word does in times of crisis:
He made them up.
Yes, he made up over 3,000 words, although many of them didn't catch on, as it were ("unhair" being my particular favorite of the archaics), and today we've incorporated around 1200 of them in one form or another. Of course, today our language is far from sparse (just ask Webster 1913!), but here for your posterity is a lengthy list of the words Shakespeare is credited with inventing:
If you want, you can pick up a book entitled Coined By Shakespeare by Jeffrey McQuain and Stanley Mallessone, which has the history behind each word.
See also: