Due to the COVID-19 pandemic, many seminars are now held online. Many of them made a YouTube channel to post their videos. But it is very difficult to search for such videos. In this post, I’d like to share a few of them. Please suggest more in the comment.

- IBS Discrete Mathematics Group
- Department of Combinatorics and Optimization at University of Waterloo
- Oxford Discrete Mathematics and Probability Seminar, Oxford University
- Laboratory of Combinatorial and Geometric Structures, MIPT
- Discrete Math Seminar at the University of South Carolina
- Discrete Math Seminar at the Simon Fraser University
- ACO Program, Georgia Tech
- SCMS Combinatorics Seminar, Shanghai Center for Mathematical Sciences, Fudan University (on Bilibili.com)
- PIMS-UVic Discrete Math Seminar (on mathtube.org)
- Graphs and Optimization seminar, LaBRI (on its own server)

Here’s a list of YouTube channels for online seminars.

- Frontiers of Parameterized Complexity
- Webinar in Additive Combinatorics
- EPC-Webinar
- Northeast Combinatorics Network
- TCS+
- CMSA Combinatorics Seminar
- Séminaire virtuel de théorie des graphes et combinatoire en Rhône-Alpes et Auvergne (video hosted on its own server)

Here’s a list of some recent conferences or workshops posting videos online.

- ALGO2020 (including ESA2020)
- HALG2020
- STOC2020, STOC2021
- FOCS
- ICALP2020 and LICS2020
- MFCS2020
- Probabilistic Combinatorics Online 2020, September 2020 (on twitch)
- New Perspectives in Colouring and Structure, March 2020 (BIRS workshop)
- International Conference on Number Theory and Discrete Mathematics (ICNTDM 2020)
- LATIN 2020

Other collections

- Informs Auctions and Market Design (AMD) Online Seminar
- Berlin Mathematics School (Vimeo) [“what is …?” seminar]
- MUNI Seminar Series (Alon’s talk on list coloring, Grohe’s talk on symmetry and similarity)
- Joint Mathematics Meetings of American Mathematical Society and Mathematical Association of America