In computing, an application programming interface (API) is an interface that defines interactions between multiple software applications or mixed hardware-software intermediaries. It defines the kinds of calls or requests that can be made, how to make them, the data formats that should be used, the conventions to follow, etc.
If you have ever used a PayPal to pay for something then you have utilized an API. Just like with logging-in for any other online service, the Pay with PayPal functionality is built with APIs to ensure that the end application can only do what it needs to, without being exposed to sensitive data or gaining access to unintended permissions.Making storing sensitive information safer for users
According to Nordicap's article, - 5 Examples of APIs We Use in Our Everyday Lives, - the inner-workings of this handy function, is very similar to the log-in process described above. When the user clicks the Pay with PayPal button, the application sends an order request to the PayPal API, specifying the amount owed and other important details. Then, a pop-up authenticates the user and confirms their purchase. Finally, if everything goes to plan, the API sends confirmation of payment back to the application. The article can be found here https://nordicapis.com/5-examples-of-apis-we-use-in-our-everyday-lives/