What does it mean?
Progressive disclosure keeps the primary experience simple while offering additional details or advanced controls at the right moment. Essential information must remain discoverable.
Make it concrete.
Illustrative example: A flight-booking page shows the total price and baggage allowance first, with detailed fare rules available when someone chooses to inspect them.
A common mistake.
Hiding information people need to make a safe decision.
When should you use it?
When an interface has meaningful complexity but users need only part of it initially.
Explore the source.
Nielsen Norman Group — Progressive Disclosure ↗This is a reference for further learning, not an endorsement or a verbatim quotation.