My mathematical writing ranges from general topology (pointset topology) to various topics in probability and statistics including topics in actuarial modeling. I also have several blogs intended for general audience.
Topology 
I have been writing in topology in a blog for many years. The blog has a great deal of contents geared toward individuals taking courses in topology (both undergraduate and graduate). On certain topics, I also go a little deeper than what a typical topology course might cover. The blog is used by both students and working topologists. 
Probability and Statistics 
There are three blogs in probability and statistics.

Actuarial Modeling 
In actuarial modeling, I write about various mathematical and statistical modeling methods that are applicable in actuarial science. I also have blogs providing practice problems and other resources for two actuarial exams (Exam P and Loss Models). 
About Me 
I earned my PhD in mathematics from Auburn University. I did my dissertation in general topology under the direction of Gary Gruenhage. Here’s my entry in math genealogy. My Erdos number is 3, through the following path:

Dan Ma math
Daniel Ma math
20172018 – Dan Ma