What is a hacker?
Definition
A hacker is a person who attempts to gain, or gains, access to a computer system without authorization. The word is also used more loosely for anyone skilled at breaking into or working around computer systems.
- Category
- Attacks
- Also called
- cracker, black hat hacker, Computer hacker
- Last updated
NIST's glossary defines a hacker as an unauthorized user who attempts to or gains access to an information system. That is the sense used in most news stories about stolen data and broken-into accounts.
In everyday talk the word covers a wider range. Some people use it for skilled programmers who like to take systems apart and see how they work. Security teams hire people to break into their own systems to find weak spots before criminals do, and these are often called ethical or white hat hackers. The permission is what separates them from a criminal hacker.
How attackers get in
Most break-ins don't involve clever code. Common routes are stolen or reused passwords, phishing messages that trick you into typing a login on a fake page, and software that hasn't been updated. For ordinary people, the usual result is a hijacked email or social account, or money taken from an account.
Hacker vs. related terms
- Hacking is the act of getting in. A data breach is the outcome when a company's data is taken.
- Social engineering persuades a person to hand over access instead of attacking the technology.
- Malware is software an attacker uses to get or keep access.
How to protect yourself
- 1
Use a different password for every account
A leaked password from one site is the easiest way into others. A password manager makes this practical.
- 2
Turn on two-step verification
Even with your password, an attacker needs your second factor. Start with your email and bank.
- 3
Install updates
Updates fix the flaws attackers use. Switch on automatic updates for your phone, computer and browser.
- 4
Don't click login links in messages
Go to the site or app directly. Phishing is the most common way people hand over their own logins.
- 5
Keep less of your info public
The more a stranger can learn about you, the easier it is to guess answers or fake a convincing message. Serus finds where your personal details are listed and removes them.
See where your personal data is exposed
Serus finds it on data brokers and people-search sites and removes it.
Frequently asked
Are all hackers criminals?
No. Hacking without permission is illegal in most places, but people who test systems with the owner's permission, often called ethical or white hat hackers, work legally.
How do I know if I've been hacked?
Warning signs include password reset emails you didn't ask for, logins from places you've never been, messages sent from your account that you didn't write and unexplained charges. Change the password and turn on two-step verification.
What should I do if my account was hacked?
Change the password from a device you trust, log out other sessions, turn on two-step verification and check recovery email and phone settings. Contact your bank right away if money is involved.
Sources
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