You might previously wondered What the heck is a Patronus?! so I am here to tell you that a Patronus, as Professor Lupin told Harry, is ‘a kind of Anti-Dementor – a guardian which acts as a shield between you and the Dementor.’ It’s also ‘a kind of positive force, a projection of the very things that the Dementor feeds upon – hope, happiness, the desire to survive – but it cannot feel despair, as real humans can, so the Dementors can’t hurt it.’
Aaaaaaaaand you can now find out what kind of Patronus you have here, or, if don’t have such a good Internet connection, here. You should know that, first of all, you have to create an account to log in on the platform. ^^
You can also find more about this topic here.
Also, if you want to buy some HP books, click here.