Asynchronous programming in JavaScript leverages features like callbacks, promises and async/await to sidestep this issue by allowing other code to run in the meantime.

We anticipate there will be other proposals.” Promises in JavaScript provide for asynchronous connection-handling, for scheduling of how code works with JavaScript APIs and functions.

At the heart of JavaScript’s asynchronous connection-handling are “promises,” which provide a new way of scheduling how your code will work with JavaScript APIs and functions.

While JavaScript itself is single-threaded, many JavaScript functions have supported asynchronous processing through callbacks (the variations on the jQuery AJAX function are just the most obvious ...