Online Math Resources:

Mikhail Khovanov's online resource page.
Johan de Jong's Stacks Project.
Geordie Williamson and Ben Elias's lecture series on Soergel bimodules and KL conjecture.

People

Mikhail Khovanov, Johan de Jong, Bernhard Keller, Guowu Meng, Aaron Lauda, Sabin Cautis , Josh Sussan, Ben Elias.

Some Notes:

[1] Lectures on McKay correspondence, handwritten notes taken by me on a special topic for an undergraduate representation theory class taught by Mikhail Khovanov, Nov, 2009.
[2] Quiver Representations and Spectral Sequences, handwritten notes taken by me ona special topic for an undergraduate representation theory class taught by Mikhail Khovanov, Mar, 2010.
[3] Complex analysis and Riemann surfaces, handwritten notes taken by me for a beautiful first year graduate course taught by D. H. Phong, 2008.
[4] Algebraic geometry, handwritten notes taken by me for an introductory first year graduate course taught by A. Johan de Jong, 2008.
[5] Lie Groups and Representation Theory, handwritten notes taken by me on an introductory graduate representation theory course taught by my adviser Mikhail Khovanov, 2008.
[6] Lectures on categorification, handwritten notes taken by me on an introductory categorification course taught by my former adviser Mikhail Khovanov. Last updated 2019.