What is black box test?

Question

I've searched through the web, but each source says differently.

So I've made two kinds of test. The first one is the 'data cycle test' from TMap and the second a input-output black box test.

Now I know that the black box test, is testing the input-output values without looking at the code.

Below is a template of a Black box test: Nr. Definition Expected value actual value

But Tmap says that blackbox test is a collection of different kinds of test techniques. Like the 'data cycle test'.

So what is blackbox test exactly? Is it ONE test technique or a collection of tests techniques? And if it is a collection of test technique, what is this expected-actual test technique called?

Answer 1

Black Box Testing:

• Approach to testing where the program is considered as a black-box.
• Testing based on solely on analysis of requirements [specification, user documentation etc.]

Also called as

1. Functional testing (Testing all the features)

2. Data-Driven Testing (Same action for different set of data)

3. I/O-Driven Testing

Black-Box testing applies to all levels of testing (e.g unit, component and system) - conducted during integration, system and acceptance testing.

Test case design methods:

Commonly used methods:

1. Equivalence partitioning: It is a process of dividing the input domain into valid/invalid classes, and for a valid input class, make the equal partition so that it will reduce the test cases.

2. Boundary value analysis: It is a process of checking the inputs on boundaries, one less than boundary and one greater than boundary.

3. Error guessing: is a ad hoc approach, based on intuition and experience, to identify the tests that are likely to expose errors.

Reference: http://en.wikipedia.org/wiki/Exploratory_testing

Answer 2

Definition:

• Black box testing is a Testing, either functional or non-functional, without reference to the internal structure of the component or system. So in this method internal structure of program is not considered, tester should provide input set to the program and test whether the program is giving expected output or not.

• This method is called as black box because, tester is not aware of the software program. Software program is like a black box; inside which tester cannot see.

BLACK BOX TESTING TECHNIQUES

Following are some techniques that can be used for designing black box tests:

• Equivalence partitioning

Equivalence Partitioning is a software test design technique that involves dividing input values into valid and invalid partitions and selecting representative values from each partition as test data.

• Boundary Value Analysis

Boundary Value Analysis is a software test design technique that involves determination of boundaries for input values and selecting values that are at the boundaries and just inside/outside of the boundaries as test data.

• Graph Based Testing Methods

Each and every application is build up of some objects. All such objects are identified and graph is prepared. From this object graph each object relationship is identified and test cases written accordingly to discover the errors.

• Error Guessing

This is purely based on previous experience and judgment of tester. Error Guessing is the art of guessing where errors can be hidden. For this technique there are no specific tools, writing the test cases that cover all the application paths.

Answer 3

I always thought of it using an analogy. Imagine you’re a mechanic testing whether a car engine works.

Black box testing is like having the hood/bonnet closed, getting in the car and pressing all the buttons and pedals and driving it around to see if it all works correctly. You might not know what type of engine is in the car or exactly how that specific engine works, but you can test whether the engine is working as you’d expect it to by messing around with all the external parts which interact with the engine.

Answer 4

Black box testing is a specification based testing. There variout black box testing techniques like: 1. Equivalence Partitioning 2. Boundary Value Analysis 3. Decision Table 4. State Transition 5. Use Case Testing

Black box testing technique is a dynamic testing technique. In this type od testing technique tester does not know about code. He or She test on the bases of input & output. In this type of testing functional and non functional testing included.