The MDN Docs never disappoint[0]. Even more details can be gotten from the author of OP's link: Exploring JS[1]. And if you're wondering why the catch block isn

The MDN Docs never disappoint[0]. Even more details can be gotten from the author of OP's link: Exploring JS[1]. And if you're wondering why the catch block isn't typed properly in Typescript, see this [2] thread. 0 - https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise https://developer.mozilla.org/en-US/docs/Web/JavaScript/Refe... 1 - https://exploringjs.com/es6/ch_async.html https://exploringjs.com/es6/ch_async.html 2 - https://github.com/microsoft/TypeScript/issues/6283#issuecomment-240804072 https://github.com/microsoft/TypeScript/issues/6283#issuecom...