A botnet is a group of Internet-connected devices, each of which runs one or more bots. Botnets can be used to perform Distributed Denial-of-Service (DDoS) attacks, steal data,[1] send spam, and allow the attacker to access the device and its connection. The owner can control the botnet using command and control (C&C) software.[2] The word "botnet" is a portmanteau of the words "robot" and "network". The term is usually used with a negative or malicious connotation.