What is the key difference between synchronous and asynchronous API calls?

The key difference between synchronous and asynchronous API calls lies in their execution behavior in relation to response time. In a synchronous API call, the process is blocked until the response is received from the server. This means that the application waits and does not continue executing subsequent code until it gets a reply. This method can be simple and easier to implement but can lead to inefficiencies, especially if the server response time is slow, as it holds up other operations.

On the other hand, asynchronous API calls allow the application to continue executing other operations while waiting for the server response. This non-blocking behavior makes asynchronous calls preferable in scenarios where responsiveness and performance are critical, as it enables better utilization of resources and allows for more fluid user interactions in applications.

Understanding this fundamental distinction is crucial for developers when designing applications that need to handle tasks concurrently without unnecessary delays.