types of defects

Types of Defects In Software Testing

As software creators, we all hope that our programs will function flawlessly. However, unforeseen issues can arise, resulting in defects.  In this post, we will discuss the types of defects in Software Testing. 

Let’s dive in!

What is a Defect?

Defects in a system or software application arise when there is any inconsistency with the product functional specification document or when the actual result doesn’t match the expected result. 

Common Types of Defects

Following are some of the basic types of defects in software development:

  1. Logical defects refer to errors made during the implementation of code. Such mistakes occur when the programmer needs a better understanding of the problem or approaches it incorrectly. Additionally, logical defects can arise if the programmer fails to consider corner cases while implementing the code. These defects are typically related to the core of the software.
  2. Syntax Defects refer to mistakes in code writing style, specifically minor errors developers make during the coding process. These defects are often caused by small symbols being missed or accidentally left out. For instance, when coding in C++, it’s possible for a semicolon (;) to be accidentally omitted.
  3. Arithmetic Defects refer to mistakes made by developers when working with arithmetic expressions or in finding solutions to such expressions. These defects are typically caused by a lack of knowledge or focus on the programmer’s part or by code congestion, making it difficult to review the written code properly.
  4. Interface Defects refer to the flaws in how the software interacts with its users. These can come in different forms, such as a complex or unclear interface or one specific to a particular platform. Proper interface testing can help identify and address these issues.
  5. Multithreading Defects: Multithreading involves executing multiple tasks simultaneously, which can result in complex debugging. Sometimes, multithreading processes may lead to deadlock and starvation, ultimately causing system failure.
  6. Interface defects refer to issues arising in software and user interaction. These defects may include complicated, unclear, or platform-specific interfaces present in various forms.
  7. Performance Defects refer to issues where a system or software application fails to meet expected results, in terms of performance i.e. how well the system performs in specific situations. It also involves the way the system responds when subjected to varying loads.
  8. Security Defect: Each defect poses a unique risk due to its inherent nature. These defects represent weaknesses that could be exploited in a security breach.

Here is a guide that talks in detail about the quality assurance in software testing

Learn More


To summarize, software defects are similar to mosquitoes on a summer evening – bothersome but unavoidable. Knowing the various types of defects, such as functional, performance, usability, and security, can assist in reducing the risks of your software application. Therefore, keep these glitches from bothering you. Instead, adopt a farseeing approach to software testing.

Happy Testing!

Frequently Asked Questions

What are examples of software defects?

Examples of software defects include logical errors that cause the program to produce incorrect results and memory leaks that lead to inefficient use of system resources.

What is an example of a functional defect?

An example of a functional defect could be a software bug that causes a program to crash when a specific action is performed. Another example could be a manufacturing defect in a product that prevents it from performing its intended function properly.

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