It doesn't matter if you're dressed up as your favorite muggle, witch, or wizard - you're all getting a big Halloween treat in the form of six (!) new stories by original "Harry Potter" author J.K. Rowling that are appearing exclusively on her sprawling Pottermore website. Yes, this is very exciting indeed.
These stories aren't exactly the most illustrative things (we were secretly hoping for a new adventure about Ron and Hermione's visit to the nearest muggle water park, but, alas, our prayers still went unanswered). Still: if you want to know some detailed backstories about various magical beings, Ministers of Magic, and the like, then please, start feasting. There's a lot to go around here; it could very well take you until trick-or-treating time to get through.
If you don't have the time and want the best bits, Vulture has run down some of the more outwardly magical bits, while, if you want to read the best story of the bunch, a detailed dossier on Ministry of Magic nightmare Dolores Umbridge, you can head on over to USA Today. The Pottermore website is amazing and intricate, especially if you want to know what house you'd eventually be sorted into, but it takes at least two degrees in Defense Against the Dark Arts to navigate the thing. Think of these shortcuts as magical spells, getting you from here to there! Or... it's like taking the fastest Knight Bus around!