Harry potter
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The Realm of the Elderlings series by Robin Hobb. She makes amazing characters and I recommend it to any fantasy lover.
"The Name of The Wind" by Patrick Rothfuss (and the actual series - just note that we are still waiting on the last book, but have patience)
The "Legends of The First Empyre" series by Michael J. Sullivan (most people will say that the Riyeria Revelations are the best, and they are set in the same world, but the Revelations were the first series that he wrote and you can see his writing style really develop and become more powerful and gripping with his more recent books. If you choose to read this, make sure you decide on what order you want to read them in. Look it up! There's a reason I'm saying this.)
"The Great Library" series by Rachel Caine
And so, so many more. I can't really choose just one.