01 / THE IDEA
What does it mean?
An affordance is a possibility for action that depends on both the person and the object or environment. In an interface, a list can allow reordering, while the drag handle signals how to do it.
02 / IN PRACTICE
Make it concrete.
Illustrative example: A control supports selecting an option. Its label and appearance help communicate that possibility; those cues are signifiers.
03 / WHAT TO WATCH FOR
A common mistake.
Calling a visual cue an affordance without distinguishing the possible action from the signifier.
04 / WHEN IT HELPS
When should you use it?
When checking which actions an interface supports and how people discover them.
05 / FURTHER READING
Explore the source.
Don Norman · 2008 ↗A reference for further learning, not an endorsement or verbatim quotation.