As a lover of mathematics, I loved this map detailing all the various mathematic topics and subtopics. Domain of Science has done a few other maps including one for engineering which I covered a few months ago. Get to know a brief history of maths, maths in the modern day, numbers, geometry, applied maths, group theory and some physics too (because you can’t have one without the other!)
Maths related: Dr. Dóminique Kemp: the first Black mathematics PhD graduate at Indiana University, a mathematician explaining infinity in 5 minutes, and why mathematics doesn’t have a replication crisis like other fields