Push notifications are messages that pop up on a user’s mobile phone or desktop device via their chosen web browser. These little banners slide into view — whether or not your app or website is open.

Push notification can also be used to authenticate a user silently without requiring their active participation in the authentication process as is the case with token-based methods. All a user needs to do is click a button to either approve or deny access to an account.

The Twilio Verify Rest API allows you to verify that a user has a claimed device in their possession. This device will receive a verification code that could be used to authenticate a user into an account. You can choose what channels you'd like to use to verify a user of an application, either via SMS, voice, WhatsApp or email.

Two-factor authentication (2FA) is a security protocol that protects users by asking them to verify their identity using two methods of authentication. Organizations use 2FA techniques to safeguard their clients' data from unauthorized access.

Time-based one-time password (TOTP) is one method of implementing two-factor authentication where users are required to not only provide their passwords, but also a time-bound numeric token sent to their device. The token is counter-checked against a generated token before access is granted.

User authentication is a method that keeps unauthorized users from accessing sensitive information. Depending on the application, user data may be limited to only those with access to an account.

Typically, users are identified by their username, email, phone number, or password. The most basic form of user authentication is the password-based type. However, due to several reasons, this method does not guarantee the security of a user's account.

There are several other technologies we can utilize to help ensure that a user of an online application is safe from exposure and potential damage. In this article, we will look at a few methods that can be implemented in Flask to ensure data safety.