Software testing involves various testing techniques. One of these is *backward compatibility testing*.

**Backward compatibility testing** is a subtype of *compatibility testing* that focuses on testing the old or previous versions of an application or software.

Backward testing is relatively easier and faster than *forward testing*, as everything is already developed in the previous version. In contrast, forward testing involves checking the upcoming and current changes in the software.

# Why perform backward compatibility testing?

We perform compatibility testing to check the capability of our application, including whether it can run on various platforms, hardware, operating systems, and technologies. 

These characteristics are inherited by *backward testing* too, in order to verify that the behavior and response of the new version of the software is working correctly with functionalities from previous versions.

This technique is quite effective for the stability and manageability of the software under test.

# How to perform backward testing

Various tools and technologies are available online to conduct backward compatibility testing on software. A few of them are listed below:

- TestProject
- Functionize
- BrowserStack
- Virtual Desktops

With the help of such tools, we can efficiently perform backward testing and save a lot of maintenance costs, update costs, time, and resources.

# Example

Suppose we are working on MS Word version 2007 and have uploaded various images, charts, and content in the document. Microsoft has updated Word to version 2013. 

Technically, everything from the previous version should be the same in the newer version. To confirm whether the previous version works perfectly well along with the newer, we have to perform backward compatibility testing.

Facebook, as an example, works effectively on all cross-browser and OS platforms, including Mac, Linux, Windows, iOS, Android, etc.

What is backward compatibility testing in software testing?

Software testing involves various testing techniques. One of these is backward compatibility testing. Backward compatibility testing is a subtype of compatibility testing that focuses on testing the old or previous versions of an application or software. Backward testing is relatively easier and faster than forward testing, as everything is already developed in the previous version. In contrast, forward testing involves checking the upcoming and current changes in the software. 