Software Bugs

Hello all, Thamsil Ahmed here. So today I will be talking about the different kinds of bugs found during software testing and their severity.

Over the past few years, ICT has played an important role in a lot of aspects of modern businesses. ICT is an abbreviation for Information, Communication, and Technology. It is a broad term that encompasses the use of computers and other electronic devices (e.g., smartphones) to perform all forms of information processing.

Before all of that, what is exactly a software bug? Mistakes in software basically. Mistakes that hinder the functioning of the software. Do you know why the word “bug” is used for these mistakes? I have already mentioned this in my previous article and would like to talk about it here as well in brief. So basically, the word “bug” got into the world of software because of an actual bug!! Back in 1947, Grace Murray, a scientist, working on the Mark II computer, noticed a moth stuck in the relay of the computer which prevented it from functioning properly, and ever since mistakes in software begin to be referred to as bugs.

Now let’s talk about the major categories of bugs. I will try to explain in it shortly with an example for each.

Usability bugs

These kinds of bugs are considered tragic for any software, as it hinders the operation of the software and creates a negative impact on the user’s experience. Example: a bug that prevents the user from logging in.

Security bugs

This is also considered a very serious bug as data associated with the software is at risk, making it vulnerable to attacks. These kinds of bugs can be exploited to get unauthorized access or data and must be fixed immediately. Example: a bug that leaks user data like usernames and passwords.

Compatibility bugs

These bugs are referred to as bugs that do not work properly across different devices and versions. Software working fine on an older OS version, may not work as expected in newer versions when the software is not updated regularly. Example: a function working perfectly in Android 10 may not work as expected in updated versions.

Performance bugs

As the name suggests, it is related to the performance of the software. It affects the stability and speed, thus affecting the overall performance of the software. Example: increasing loading time, lags.

Functional bugs

This is when a function in the software doesn’t work as intended. For example, a delete button, when clicked does not delete the record.

Unit level bugs

These bugs do not cause much damage to the software and are very easy to fix. For example, count of photos in a file is displayed wrong.


Now let’s talk about the severity of bugs.

Bugs are considered to be of less severity when there is no hindrance to the functioning of the software. Unit levels bugs are an example.

Bugs are considered to be of medium severity when there is a little bit of hindrance to the functioning of the software. These bugs need to be fixed for a better user experience. Example: Performance bugs

Bugs are considered to be of high severity when a functionality doesn’t work as expected i.e., unexpected behavior. These kinds of bugs can sometimes completely damage the functioning of the whole software. Example: Usability bugs

Bugs are considered to be of critical severity when the functioning of the software is completely impeded. These kinds of bugs can also make the testing process difficult. Example: some usability bugs and security bugs.

I hope these things help you during your next test. Thanks for reading and happy testing!!!

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