A Promise represents a future value (pending/fulfilled/rejected) and supports chaining with then/catch. Callbacks are functions passed to be invoked later, often leading to nested code.
Advanced answer
Deep dive
Expanding on the short answer — what usually matters in practice:
Context (tags): promises, async
Explain the "why", not just the "what" (intuition + consequences).
Trade-offs: what you gain/lose (time, memory, complexity, risk).
Edge cases: empty inputs, large inputs, invalid inputs, concurrency.
Examples
A tiny example (an explanation template):
// Example: discuss trade-offs for "how-do-promises-work-and-how-do-they-differ-from"
function explain() {
// Start from the core idea:
// A Promise represents a future value (pending/fulfilled/rejected) and supports chaining wit
}
Common pitfalls
Too generic: no concrete trade-offs or examples.
Mixing average-case and worst-case (e.g., complexity).