This post is about what I have learned about visualizing data from 2019nCov-api. In order to visualize the data I will need to get the latitude-longitude reference. And I found two interesting APIs. Baidu Map vs Google Map. The coordinate systems is actually quite interesting. Baidu Maps uses a variant of web Mercator projection for slicing map data into tiles with an underlying latitude-longitude reference - BD-09 coordinate system while the Chinese government is using GCJ-02.