An application programming interface (API) lets programs or applications interact with each other. They allow you to use a software's code without using its user interface (UI). Not all applications have an API; developers must build them.
When you use the UI, you manually click ‘New Loan’ and type everything in. When using the API, your software will generate a little bundle of information with all the necessary loan specifics and send it to a designated URL. LoanPro will receive that information at the URL, and use it to create a new loan. LoanPro will send back a response saying that your loan was successfully created. Both the UI and API use the same code and enter the same information, but the API allows you to use a separate software rather than manually clicking buttons.
The purpose of an API is to allow programs written in different programming languages to communicate with each other and ensure that data can be safely sent and received from a proprietary application without having to give away access to the application’s code base.
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