Types Of Testing

There are many ways in which software testing can be categorized. Some of them are described as follows:
Categorization of testing based on the knowledge of system

• Black Box Testing
• White Box Testing
• Gray Box Testing

Categorization of testing based on the time it is executed in the Software Development Life Cycle

• Unit Testing
• Integration Testing
• System Testing
• User Acceptance Testing

Different types of testing can be categorized based on the purpose of testing. This can be classified further into Functional Testing and Non Functional Testing.

• Functional Testing

In functional testing, the focus of testing activities is on functional aspects of the system. In functional testing, test cases are written to check the expected output. Functional testing is normally performed in all the test phases from unit to system testing.

The following types of test activities are normally performed under Functional Testing


• Installation Testing
• Regression Testing
• Upgrade and backward compatibility testing
• Accessibility testing
• Internationalization and localization testing
• API Testing


• Non-Functional Testing

In non-functional testing, the focus of the testing activities is on non functional aspects of the system. Non functional testing is normally carried out during the System Testing phase only. The focus of non functional testing is on the behavior and user experience of the system.


• Performance, Load and Stress Testing
• Usability Testing
• Security testing
• more to come..

Bug Impacts

Low impact
This is for Minor problems, such as failures at extreme boundary conditions that are unlikely to occur in normal use, or minor errors in layout/formatting. These problems do not impact use of the product in any substantive way.

Medium impact
This is a problem that a) Effects a more isolated piece of functionality. b) Occurs only at certain boundary conditions. c) Has a workaround (where "don't do that" might be an acceptable answer to the user). d) Occurs only at one or two customers. or e) Is very intermittent

High impact
This should be used for only serious problems, effecting many sites, with no workaround. Frequent or reproducible crashes/core dumps/GPFs would fall in this category, as would major functionality not working.

Urgent impact
This should be reserved for only the most catastrophic of problems. Data corruption, complete inability to use the product at almost any site, etc. For released products, an urgent bug would imply that shipping of the product should stop immediately, until the problem is resolved.

10 Rules Of Software Testing

1. Test early and test often.

2. Integrate the application development and testing life cycles. You'll get better results and you won't have to mediate between two armed camps in your IT shop.

3. Formalize a testing methodology; you'll test everything the same way and you'll get uniform results.

4. Develop a comprehensive test plan; it forms the basis for the testing methodology.

5. Use both static and dynamic testing.

6. Define your expected results.

7. Understand the business reason behind the application. You'll write a better application and better testing scripts.

8. Use multiple levels and types of testing (regression, systems, integration, stress and load).

9. Review and inspect the work, it will lower costs.

10. Don't let your programmers check their own work; they'll miss their own errors.