  While social media are a key source of data for computational social science,
their ease of manipulation by malicious actors threatens the integrity of
online information exchanges and their analysis. In this Chapter, we focus on
malicious social bots, a prominent vehicle for such manipulation. We start by
discussing recent studies about the presence and actions of social bots in
various online discussions to show their real-world implications and the need
for detection methods. Then we discuss the challenges of bot detection methods
and use Botometer, a publicly available bot detection tool, as a case study to
describe recent developments in this area. We close with a practical guide on
how to handle social bots in social media research.
