What does hacking do?

Hacking is the act of finding and exploiting weaknesses in computers, networks, software, or devices to gain access, control, or information. It can be used for legitimate purposes, such as security testing, vulnerability research, and improving defenses, when performed with authorization, or for malicious ends like data theft, financial fraud, service disruption (DDoS), spying, or installing malware.

Techniques range from social engineering and phishing to exploiting software bugs, misconfigured systems, or weak credentials. The effects of hacking vary from minor privacy breaches to large-scale financial loss, reputational damage, and threats to public safety, depending on the attacker’s intent and the target. Defensive measures—patching, strong authentication, network segmentation, monitoring, and security training—help reduce the risk and impact of hacking.