Authentication

What is Authentication?

Authentication is the process of verifying the identity of a user, device, or system.

Expanded Explanation

Authentication ensures that access is granted only to legitimate users. It can be single-factor (password), two-factor (2FA), or multi-factor (MFA) and is central to any secure system.

Related Terms

2FA, MFA, Identity Management, Password Security, Biometrics

Want to learn more?

If you’re interested in Authentication, we recommend: Cloud-Based Hacking: Hack Logins, Computers & More

Check out our Online Ethical Hacking Courses.

✅ Lifetime access to lessons
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✅ No programming or hacking experience needed.
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Zaid Sabih
Zaid Sabih

Ethical Hacker, Pentester & Computer Scientist

Zaid Al-Quraishi is an ethical hacker, computer scientist, and founder of zSecurity. He studied CS at UCD, graduating May 2016.

Zaid has a strong background and experience in ethical hacking, starting with tutorials in 2009 in an ethical hacking community, iSecur1ty. He also worked as a penetration tester (pentester) for this company.

In 2013 he started teaching his first course online in Arabic which received extremely positive feedback. This motivated him to create an English version of the course. The English course became the most popular and top paid course on Udemy for almost a year, which further motivated Zaid to design and teach more courses on ethical hacking.

He now offers a number of courses on ethical hacking and more than 800,000 students on Udemy and other teaching platforms such as StackSocial, StackSkills and zSecurity.

Zaid says: "I just love hacking and breaking the rules but don't get me wrong, I am an ethical hacker!"

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