Each node is a person and their tweet, those who answered more similarly get connected (Graphext dimensionality reduction algorithm calculate a similarity score) In the extremes you find people that mentioned the same language for all the categories), like Ryan Florence

The question that correlates more with the rest of is about what is the programming language is more used. In the image we can see a clear map of web developers on the right (Javascript, PHP, Ruby) and data scientists on the left (R, Python) and C/C++, Java in the middle.