Earlier this week, Spain’s highest court agreed to extradite Peter Levashov who was indicted last April by a federal grand jury on charges of fraud, identity theft and conspiracy.  Levashov who formerly served in the Russian army and also had  worked for Russian President Vladimir Putin’s United Russia Party is accused of operating a massive botnet of thousands of infected computers that he would rent out to other criminals to send computer viruses and malware.
A botnet is a network of computers that have been infected with malware that enables criminals to surreptitiously use these computers to send out all manner of malware including ransomware.  People whose computers become part of a botnet often unwittingly download the malware necessary to make their computer part of the botnet by clicking on a link in an infected phishing email.
TIPS
Many people are a part of botnets without even knowing it.  If you use Windows 10 you can find out if you are a part of a botnet by opening the Task Manager and see what programs are using your network.  If there is something you don’t recognize, you may be a part of a botnet.
Of course, the best course of action is to avoid ever becoming part of a botnet and the best way to do that is to avoid clicking on any links in any emails unless you have absolutely confirmed that the email is legitimate.  In addition, installing security software and keeping it up to date with the latest security patches is also a good practice and if your router is more than ten years old, it may not be providing sufficient protection from botnets.  Updating old routers can help avoid becoming a part of a botnet.