What is the difference between synchronous and asynchronous functions?

I/O operations are the most common application of synchronous functions. They respond instantly to data flow in the server and keep up with the data as required. If no replies are received, the API will return an error.

Asynchronous functions, on the other hand, work because they are not synchronous, as the name implies. When HTTP requests are pushed, they will not wait for a response to start before proceeding. Even if the server has already received the response, the server will continue to respond to prior requests.