Simple explanation
The price of borrowing and reward for lending. It becomes visible whenever people must choose among alternatives.
Go deeper
Understanding this concept means asking what changed, what constraints apply, and which alternatives remain available. Its meaning becomes clearer when connected to real decisions.
FACT
Evidence and context are labeled clearly.
INTERPRETATION
Evidence and context are labeled clearly.
CONSENSUS
Evidence and context are labeled clearly.
Related concepts
Sources & further reading
Reviewed September 2026 · Editorial standards applied