1
JavaScriptIntermediate#dom#events
JavaScriptBeginner#async
What is callback hell and how do you avoid it?
Deeply nested callbacks that become unreadable and hard to error-handle. Flatten it with named functions, promises, or async/await.
Example
// callback hell getUser(id, u => getOrders(u, o => getItems(o, i => render(i)))); // modern const u = await getUser(id); const o = await getOrders(u); render(await getItems(o));