information graphics - What are these line and dot graphs called?

I am looking for some kind of minimalistic network graphs but I can't find the right words to describe them.

A while ago, I discovered a webpage that has these kind of graphs but I no longer find it.

I have tried terms such as: "big data visualization", "network graphs", "design network graphs", "stock network graphs"...

An example of what I am looking for:

Or the background logo used on this site itself:

I am just looking for a graph (minimalistic or flat design) with lines and nodes.

This is a similar website that I found:

http://personalbrandinstitute.com/