- Know how to create promise.
new Promise( (resolve, reject ) => { })Promise.resolve(<resolved_value>)Where<resolved_value>can be any value, even another promise.Promise.reject(<error_value>)
promise.then( resolved_value => return <x> )Where<x>either becomes the newresolved_valuefor next.thenor if it's a promise, it becomes the new promise in the chain. Remember to return your promise!