Two-step verification adds a second secret after the main login step, usually a password or passkey. That second factor may be a code, PIN, or recovery secret, and it is meant to prove that the person signing in has more than just the primary credential. In account security, 2SV matters because stolen passwords are common, but a second check can stop many simple takeover attempts.
In real attacks, criminals try to bypass 2SV by phishing the second code, intercepting SMS, abusing account recovery, or tricking users into revealing it during a fake support call. Good defenses use stronger second-step secrets, app-based or phishing-resistant methods, and well-controlled recovery paths. 2SV is not perfect, but it raises the cost of unauthorized access and reduces the impact of leaked or reused passwords.