The Promise is an Object introduced in ECMA Script 2015 as part of 6th Edition. It represents the future completion of Success / Failure Operation. It mainly helps to works smoothly with asynchronous operations. Promise API is mainly followed Promises/A+ Specification.
For Instance, You have submitted the email form / search form and waiting for the response. In that case, you will not be sure when server will respond and its bit hard to predict the time and get the actual message after that particular execution time for the response. Promise can help to fix this issue.
Take a look at below snippet which uses Promise API where it catches the success message after few seconds and you can increase time in setTimeout method as well but console triggers whenever its get the message. In this example, We used timeout function to return after few seconds like server response.
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