What are promises and what is the difference between Promise.all, Promise.allSettled, Promise.race and Promise.any?
Callback: A callback is a function that is passed into another function as an argument to be executed later.
Events: Events provide a dynamic interface to a WebPage and are connected to elements in the Document Object Model(DOM), for example: onclick(), onmouseover() etc.
Pending: Before the event has happened, the promise is in the pending state.
Settled: Once the event has happened it is then in the settled state.
Fulfilled: Action related to the promise has succeeded.
Rejected: Action related to the promise has failed.
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