Propaganda bots made a powerful showing during Election 2016. Oxford University’s Project on Computational Propaganda found that at times during the campaign, more than a quarter of the tweets colonizing politicized hashtags like #MAGA and #CrookedHillary came from “heavily automated accounts.” In the days leading up to the election, Trump propaganda bots outnumbered Clinton propaganda bots five to one. Since then, bot armies have been programmed to spread conspiracy theories about a made-up Democratic pedophile ring known as Pizzagate. The bots help the topic trend, lend an air of grass-roots momentum and create enough of a mirage of a movement that real people then join in.

Bots of conviction can’t compete with those numbers — spamming is not their style — but they can work as effective tools of provocation, as this taxonomy shows.