This document provides an introduction to software testing, outlining key definitions, principles, and types of testing. Software testing is described as a process aimed at finding bugs to ensure a software product meets specified requirements. It highlights differences among errors, defects, and failures, and discusses the importance of structured test cases, including methodologies like black-box and white-box testing.

1. Lesson-1
Introduction to Software Testing
By
Syed Usman Ahmed

2. Modules in Lesson-1
• Basic definitions and terminologies of software testing.
• Principles of Software Testing
• Basic types of testing.
• White box testing.
• Black box testing.

3. Basic definition - Software Testing
SOFTWARE TESTING
• Software testing is a process of executing a program or application with the
intent of finding the software bugs.
• It can also be stated as the process of validating and verifying that a
software program or application or product: Meets the business and
technical requirements that guided it's design and development.

4. Basic Definition - Error and Fault (Defect)
ERROR
• An error is a mistake, misconception, or misunderstanding on the part of
software developer.
FAULT (DEFECT)
• A fault or defect is introduced into the software as the result of an error. It
is an anomaly in the software that may cause it to behave incorrectly, and not
according to its specification.

5. Failures
• A failure is the inability of a software system, or component to perform its
required functions within specified performance requirements.
Question for viewer
What is the difference between error and defect?

6. Test Cases
• A test case in a practical sense is a test-related item which contains the
following information:
• A set of test inputs: These are data items received from an external source by the code
under test. The external source can be hardware, software, or human.
• Execution conditions: These are conditions required for running the test, for example
a certain state of a database, or a configuration of hardware device.
• Expected output: These are specified results to be produced by the code under test.

7. More definitions
• Test – A test is group of test cases, or a group of related test cases and
test procedures.
• Test Oracle – It is a document, or a piece of software that allows testers to
determine whether a test has been passed or failed.
• Test Bed – A test bed is an environment that contains all the hardware
and software needed to test a software component or a software system.

8. Principles of Software Testing
• Principle 1: Testing is a process of exercising a software component using a
selected set of test cases, with the intent of (i) revealing defects, and (ii)
evaluating quality.
• Principle 2: A good test case is one that has probability of revealing a yet
undetected defect(s).
• Principle 3: Test results should be inspected meticulously.
• Principle 4: Test case must contain the expected output or result.

9. Principles of Software Testing
• Principle 1: Testing is a process of exercising a software component using a
selected set of test cases, with the intent of (i) revealing defects, and (ii)
evaluating quality.
• Principle 2: A good test case is one that has probability of revealing a yet
undetected defect(s).
• Principle 3: Test results should be inspected meticulously.
• Principle 4: Test case must contain the expected output or result.

10. Principles of Software Testing
• Principle 1: Testing is a process of exercising a software component using a
selected set of test cases, with the intent of (i) revealing defects, and (ii)
evaluating quality.
• Principle 2: A good test case is one that has probability of revealing a yet
undetected defect(s).
• Principle 3: Test results should be inspected meticulously.
• Principle 4: Test case must contain the expected output or result.

11. Principles of Software Testing
• Principle 1: Testing is a process of exercising a software component using a
selected set of test cases, with the intent of (i) revealing defects, and (ii)
evaluating quality.
• Principle 2: A good test case is one that has probability of revealing a yet
undetected defect(s).
• Principle 3: Test results should be inspected meticulously.
• Principle 4: Test case must contain the expected output or result.

12. Principles of Software Testing
• Principle 5: Test cases should be developed for both valid and invalid input
conditions.
• Principle 6: Testing should carried out by a group that is independent of the
development group.
• Principle 7: Tests must be repeatable and reusable.
• Principle 8: Testing should be planned.

13. Principles of Software Testing
• Principle 5: Test cases should be developed for both valid and invalid input
conditions.
• Principle 6: Testing should carried out by a group that is independent of the
development group.
• Principle 7: Tests must be repeatable and reusable.
• Principle 8: Testing should be planned.

14. Principles of Software Testing
• Principle 5: Test cases should be developed for both valid and invalid input
conditions.
• Principle 6: Testing should carried out by a group that is independent of the
development group.
• Principle 7: Tests must be repeatable and reusable.
• Principle 8: Testing should be planned.

15. Principles of Software Testing
• Principle 5: Test cases should be developed for both valid and invalid input
conditions.
• Principle 6: Testing should carried out by a group that is independent of the
development group.
• Principle 7: Tests must be repeatable and reusable.
• Principle 8: Testing should be planned.

16. Types of Software Testing
Software
testing
Black-Box
User-
Inputs
Expected-
Outputs
White-Box
User
Inputs
Expected
Output
Internal
Structure

17. Black-Box (BB) Testing
• Black-box testing is a method of software testing that examines the
functionality of an application without peering into its internal
structures or workings.
• This method of test can be applied to virtually every level of software
testing: unit, integration, system and acceptance.
• Boundary Value Analysis (BVA) and Equivalence Partitioning (EP) are
two basic types of Black Box testing.

18. White-Box Testing
• White-box testing (also known as clear box testing, glass box testing,
transparent box testing, and structural testing) is a method of testing
software that tests internal structures or workings.
• This method of test is generally applied at the beginning of the software
development i.e. at the development of every unit.
• Software developer does the white box testing.

19. Thanks