Explain in detail about Black box testing.

• Black box or behavioural testing focuses on the functional needs of the software.
• It is applied during the last phase of testing.
• Syntax driven testing is suitable for the specification which are explained by a certain grammar.
• Decision table based testing is executed when the original software requirement have been formulated in the format of " if-then" statements.
• Liquid level control is the study of a simple control problem which is intended to check the liquid level. It has 2 sensors.