Hacker

What Is a Hacker?

A hacker is a person who uses technical knowledge to access, exploit, or modify computer systems and networks, often by bypassing security measures.

Types of Hackers

Security hackers are commonly grouped into three categories based on their intent and whether they have permission to access a system. The labels come from old Western films, where a white hat marked the hero and a black hat marked the villain. In practice, the main line separating them is authorization.

White hat hackers

White hat hackers, also called ethical hackers, test systems with the owner's permission to find and help fix vulnerabilities before others can exploit them. Some work as full-time security staff, while others take part in bug bounty programs or hacking competitions that reward each valid flaw they report. Many hold qualifications in information security or computer science.

Black hat hackers

Grey hat hackers

Grey hat hackers sit between the above two groups. They often access systems without permission but not necessarily for malicious gain. A grey hat might discover a vulnerability and report it to the owner, sometimes requesting a fee to help fix it. However, even when their intentions seem constructive, accessing a system without authorization can still be illegal. Hacktivists, who are motivated by political or social causes, are sometimes placed in this category.

Why the Distinction Matters

White hat and black hat hackers frequently use the same tools and techniques, so the deciding factor is whether the access was authorized and within an agreed scope. Artificial intelligence has added complexity for all three groups, as it can make certain attacks faster and more accessible while also strengthening the defenses used to detect them. For this reason, ethical hacking has become an increasingly important part of protecting systems and user funds.