Async/Await in JavaScript: From Callbacks to Clean Code JavaScript's evolution from callback hell to clean async code. The Evolution Stage 1: Callbacks (The Dark Ages) // Callback hell: nested, hard to read, error-prone getUser ( id , ( user ) => { getPosts ( user . id , ( posts ) => { getComments ( posts [ 0 ]. id , ( comments ) => { getAuthor ( comments [ 0 ]. authorId , ( author ) => { console . log ( author . name ); // Error handling? Good luck. }); }); }); }); Enter fullscreen mode Exit fullscreen mode Stage 2: Promises (Better) // Flat chain but still verbose getUser ( id ) . then ( user => getPosts ( user . id )) . then ( posts => getComments ( posts [ 0 ]. id )) . then ( comments => getAuthor ( comments [ 0 ]. authorId )) . then ( author => console . log ( author . name )) . catch ( err => console . error ( ' Something failed: ' , err )); Enter fullscreen mode Exit fullscreen mode Stage 3: Async/Await (Modern) // Reads like synchronous code!…