Relative to the Russia/Trump special investigation, I've heard it said the Russians use "Bots" or "ad-Bots" to stoke division on both sides through thousands of social media accounts.

https://en.wikipedia.org/wiki/Twitter_bot

I still barely understand the concept. Except that it is a program that automatically sends out Twitter posts and re-posted content, to spread propaganda.

I was surprised that there are positive aspects too, such as a Wikipedia bot that notifies them when Wikipedia is edited by someone with a U.S. Senate/Congress IP address, or a British Parliament address. Although that could have a downside that it allows their political opposition to edit/propagandize Wikipedia in their favor, while not allowing government officials to do the same or respond.