Authenticator app is a Two Factor Authentication (2FA Authentication) which generates Time-based One-time Passwords (TOTP) and PUSH authentication. It helps keep your online accounts secure on supporting TOTP websites.

The generated codes are one time tokens that provide an extra layer of security to your online accounts. After scanning a simple QR code, your account is protected. Using 2FA Authenticator helps keep your online accounts secure on supporting TOTP websites.
Also you can secure your one time tokens with password protection.