Black box testing is a testing method that evaluates software functionality without accessing internal code.

Explanation:

• Testers only know inputs and expected outputs.
• Used for functional, system, and acceptance testing.
• Common techniques:
  • Equivalence Partitioning (grouping inputs).
  • Boundary Value Analysis (testing edge cases).

Example:

• A login page:
  • Valid Input → User logs in successfully.
  • Invalid Input → Error message displayed.