From the earliest days of software development, authentication (also called auth) has been essential. To ensure system and data security, you must ensure that only properly identified users are permitted to log in to a system.
If you’re building native integrations to connect your SaaS product to the other apps your customers use, one of the tricky pieces is dealing with the nuances of the third-party apps, such as authentication. Sometimes you'll be the one setting up authentication for your own app, and sometimes you'll need to configure your integrations to use whatever auth pattern has been provided. In either case, knowing how user authentication methods work and what to look for can save you time and prevent integration headaches.