What does malware do? There are many answers but one is to co-opt your computer for a DDos (or Distributed Denial of Service) attack on a target chosen by cybercriminals.
Hackers and cybercriminals are always up to various kinds of no-good. Sometimes they want access to your computers and devices to bombard you with annoying ads, sometimes to steal and sell your valuable information, and sometimes to use your computer to help them do their dirty work.
DDoS is short for Distributed Denial of Service, which occurs when an army of malware-infected computers all flood a target with activity, overwhelming the target and rendering it inoperable. For example, say cybercriminals want to shut down a popular online retailer. To do so, they might infect thousands of random computers with malware that they use to bombard the retailer with activity until the retailer’s servers overload and shut down.
The best way to protect yourself from malware, and avoid being part of a DDoS attack, is to keep your cybersecurity up to date, protect your passwords, and avoid websites and streaming services that offer pirated content.