TITLE: Great graduate courses that went online recently
QUESTION [186 upvotes]: In 09.2020 by pure chance I discovered the YouTube channel of Richard Borcherds where he gives graduate courses in Group Theory, Algebraic Geometry, Schemes, Commutative Algebra, Galois Theory, Lie Groups, and Modular forms! (and an undergraduate courses in Theory of numbers and Complex analysis).
I watched so far about 300 of his videos (about 90%) and they are really great. Borcherds is an amazingly good lecturer (for my taste). It is also clear, that these lectures were worked out/improved through years, since Borcherds was giving similar ones in Berkeley (one can find some lecture notes by students online). I would guess, that currently there are some other great lecturers that started to upload their courses on YouTube (or some other platforms). For this reason a question.
Question. If you watched recently an online graduate course (free for all), and found it brilliant, by a lecturer whom you find great, and believe that the course taught you something, could you please share  the info about it.
The motivation for this question is to spread information about exciting things happening in mathematical life/education lately.

REPLY [3 votes]: Here we go again.

Integration Theory by Professor Marcus Carlssons, link: https://youtu.be/EzoaGgBHJEQ

Graduate Real Analysis by Professor Emanuel Carneiro, link: https://youtube.com/playlist?list=PLp0hSY2uBeP8hajKOVGZ9oIPjG3HKMfoY

Graduate course on “Groups and Galois Theory” by Professor Yuly Billig, link: https://youtube.com/playlist?list=PLu6jbin1VpDBGWvctA_vGFLXzJD8YsA3F

Differential topology course at IMPA by Professor Vinicius Ramos, link: https://youtu.be/yOoWugX1AOI

Introduction to Algebraic K-Theory, link: https://youtube.com/channel/UCNefIuLog1bTwR0rav3p_5A

https://youtube.com/c/UndergraduateMathematics YouTube channel is crazy. Just check out entire playlist of that channel. That channel is a window to thousand different graduate level math courses.

Introduction to Stacks and Moduli by Professor Jarod Alper, link: https://youtube.com/playlist?list=PLhFI5R_xInjdhtWuhgYlA8NZGXO-unnl4

Higher Algebra, link: https://youtube.com/playlist?list=PLsmqTkj4MGTDenpj574aSvIRBROwCugoB. Topological Cyclic Homology, link: https://youtube.com/playlist?list=PLsmqTkj4MGTB8pNGvW0iuKUFmBlOSke-C

SubRiemannian geometry course by Professor Enricole Le Donne, link: https://youtube.com/playlist?list=PLleGBpoKCrJn21-tCrNRk6JAyh4gwtgks

Area formula-Geometric Measure Theory, link: https://youtube.com/playlist?list=PL_c66HM3gCshuMPW7BgVdWg_I8OitI7mC

Category Theory by Professor Ivo De Los Santos Vekemans, link: https://youtube.com/playlist?list=PLHYBb0FtzAK9TBFhZ8eZzJRc5gW1NNp2K

Algebraic Geometry, link: https://youtube.com/c/AntonMosunov

Stanford Algebraic Geometry Seminar, link: https://youtube.com/playlist?list=PLdBhxg1X10QTkMv9XKj7h0naLhwKY-qw_