Here are the notes from a basic course on category theory. Unlike the Fall 2015 seminar, this tries to be a systematic introduction to the subject. A good followup to this course is my Fall 2018 course.
If you discover any errors in the notes please email me, and I'll add them to the list of errors.
You can get all 10 weeks of notes in a single file here:
Week 8 (Feb. 25) - Guest lecture by Christina Osborne on symmetric monoidal categories.
Where does topos theory go from here?