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Vithu Mathi
Vithu Mathi
Front End Web Development Techdegree Student 3,474 Points


Hello TreeHouse Community,

I am having a hard time understand what's a asynchronous calls? and what a asynchronous nodeJS APIs is?

Any help would be much appreciated.

1 Answer

Steven Parker
Steven Parker
215,954 Points

Asynchronous basically means "happening at the same time".

In a typical (synchronous) function call, the main program waits until the function is totally finished before it continues with the main code. But in an asynchronous call, the function just starts something but returns to the main program right away. Then the main code can continue running while the other action is happening at the same time.

An asynchronous call would typically have at least one callback argument, which would be another function it would call to indicate completion or other state change in the task it is performing.