The most common software bugs

Mistakes in software development, ranging from crashes to control flow errors, can be costly, necessitating early detection and correction.

From time to time, everyone is prone to making mistakes. Sometimes, they happen due to poor quality of work, sometimes because of a misunderstanding and sometimes because of a minor accident.

No matter what the cause, mistakes are unwanted in most cases. No matter how much you can learn from mistakes, it is still better to avoid making them. In general, mistakes can be dangerous due to the unpredictability of their consequences.

Thankfully, they can be easily spotted, especially in software development. Some bugs may be harmless and invisible, while others may cause software or applications to crash or lose data. That is why all of them should be spotted and fixed in the early stages of the software development process.

This should be a factor which is considered while choosing your software development partner. Many IT companies provide software tests and can find the bugs, but it is more effective for your software provider to run these tests as they know the code and their product the best. Specific errors can occur frequently in many IT projects, and an experienced tester should be capable of spotting them in a few moments. Below, you can find a list of some of the main types of software bugs:


This is one of the most common and sometimes dangerous types of error that could occur. It is caused by a software solution, operating system, or program not working correctly and forcing itself to shut down. It may be caused by a software bug or sometimes a hardware device and can cause much damage. If the data is not protected or stored in the cloud, it may be lost after the crash due to a lack of opportunity to save the changes.

Functional error

On the whole, it is evident when software is built correctly because it will be fully functional. But if something is wrong and the software’s behaviour varies from the expected, it is called a functional error. This is quite common and easy to spot during tests.

For example, the functionality of a ‘Cancel’ button is that the window should be closed, and none of the changes should be saved. If you cannot click the button, this is a functional error.

Acknowledgement message error

This error happens when a user is acknowledged or given feedback with the wrong or no message. There are many activities after which users should be informed of the actions that have been taken or any changes that have been made. An example of a message error is failing to provide users with a necessary email after signing into the newsletter.


Missing a single letter or a punctuation mark happens constantly; sometimes, finding out what went wrong is hard. These are some of the most common mistakes made during coding that may affect the whole functionality of the program. These bugs are not easy to spot, but it is straightforward to correct them when found.

Missing command

This particular type of bug occurs when there is a command missing. The user is expecting an action to happen or to be allowed to perform an activity. For example, when the user is in the middle of purchasing goods in an online store and changes their mind, the system does not allow them to cancel the process before finalisation. The customer expects to have the possibility to stop the process, but the software does not have an option to do so.

Calculation error

In most software processes, calculations are vital, and ensuring everything adds up correctly is important. At the same time, there is a huge field for errors to potentially occur by implementing incorrect formulas, units, logic or data types. For example, in 1999, NASA lost its Mars climate orbiter immediately after arriving at Mars. It was caused by one of NASA’s subcontractors who used English units instead of universal metric system units.

Hardware usage error

This type of error occurs when the software is used on the wrong device or in an unadjusted environment. A specific solution should adjust to multiple types of devices capable of handling all its functions. It is important to provide hardware that is adapted to the software. The wrong operating system, low computing power or a mismatched device cause some of the most common hardware usage errors.

Control flow error

The software control flow describes what will be done next and on what conditions. Errors connected to the control flow prevent software from proceeding to the following tasks correctly, which may slow down the workflow of the whole company. For example, if a user clicks the “save and next” button at the end of a questionnaire or a process and is not redirected to a new tab, it is a control flow error.

Errors, bugs and mistakes occur everywhere, and they can cause much damage if not found and fixed early, especially in the IT industry. Sometimes, missing a single comma can affect the whole IT product, and we should put pressure on detecting and fighting the bugs. Nowadays, many IT companies have testers who work long hours with every element of a new software solution to find errors and eliminate them individually. Remember this while choosing your IT partner.

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