Understanding the Differences Between Functional and Non-Functional Testing: A Comprehensive Guide

Have you ever wondered how popular applications such as Hot star and Netflix release new features without any downtime, handle millions of viewers together at a time. This all comes down to rigorous testing that goes behind. In this article you will learn about both Functional and Non-Functional Testing along with their types and where are they used.

Functional and Non-Functional Testing play a key role in Software Testing so as to ensure user requirements and performance. These are two broader approaches on which all the types of testing are classified.

Functional Testing:

Functional testing is a type of software testing in which testing is carried out on the application to check if satisfies the user requirements and specifications. It comes under the category of black box testing which means this testing does not require or depend on the source code of the application or the new feature. Each and every feature in the application is tested providing proper input and obtaining the actual output and then comparing this actual output with the expected output in the testing environment. In simple Terms, Functional testing checks what the product does and is it aligned according to the business requirements.

Types of Functional Testing:

Here is the list of common types of Functional testing:

1.Unit Testing: Unit Testing is a type of functional testing which is usually done by developers to check how different units are working. Here the units can be methods, modules, or objects. It is the first level of testing that is being done and helps in detecting uncovered defects in the initial phase of STLC thus helping in saving lot of money and time.

2.Smoke Testing: Smoke Testing is a type of functional testing which is done during the initial phases of the development of an application or software. This is done in order to check if the critical and major functionalities of the application are at least working as expected. If these tests fail that particular build is rejected and developers fix the particular bug accordingly. Smoke tests save lot of time for QA by identifying major defects and stop doing rigorous testing further. This type of testing is done on a highly unstable application.

3.Sanity Testing: Sanity Testing is a type of functional testing which is done on a stable application after many number of releases are done for the application. The tests for sanity testing are picked up from regression tests which usually cover the major functionalities of the application. Once Sanity Testing is done, next level of extensive testing is done on the particular build.

4.Integration Testing: Integration Testing is a type of functional testing which is done in which testing is done to check if two or more components or units are integrated properly or not. Since a system’s modules and components are commonly built separately by different developers, integration testing is critical to validate that they work together correctly.

5.Regression Testing: Regression Testing is a type of functional testing which is done after new alterations or features are added to the application or system. While adding new features there might be some unwanted changes are done to the application. In order find these defects regression testing is done. Usually regression tests are automated in each sprint as it more intensive and run frequently.

6.User Acceptance Testing (UAT): User Acceptance Testing (UAT) is a type of functional testing in which the user verifies whether the features or business requirements that have been agreed upon initially have been met or not. Based on the UAT user accepts or rejects the application and finally this version will be released or rolled back accordingly.

Non-Functional Testing:

Non-Functional testing is a type of software testing in which testing is carried out to test the application’s Non-Functional Requirements such as performance, scalability, and reliability. Non-Functional tests how the application or software behaves in different circumstances and situations and how does it handle. It is done once the functional testing is done and it is done with the help of some tools such as JMeter by creating real time situations. In simple Terms, Non-Functional testing checks the performance of the software in various conditions.

Types of Non-Functional Testing:

Here is the list of common types of Non-Functional testing:

1.Performance Testing: Performance testing is a type of software testing that is used to determine how a system or application performs under specific conditions and loads. This type of testing is used to evaluate the speed, responsiveness, stability, scalability, and resource utilization of the software. It helps in identifying bottlenecks, slow or delayed responses. The performance expectations need to be mentioned in SRS document to make a comparison with the actual performance.

2.Load Testing: Load Testing is a type of non-functional testing which is done to check how the application performs while we increase the load and how the application performs at the peak of load. The goal of load testing is to identify the maximum capacity of a system or application, measure its response time, and evaluate its performance under varying levels of user traffic and workload.

3.Stress Testing: Stress Testing is a type of non-functional testing that evaluates a system’s ability to handle extreme loads and stressful conditions beyond its normal operating capacity. The goal of stress testing is to identify how a system behaves under unfavorable or unexpected conditions, such as high user traffic, insufficient resources, or system failures.

4.Compatibility Testing: Compatibility Testing is a type of non-functional testing that evaluates how well the application performs with different types of hardware and software platforms. The goal of compatibility testing is to identify how the application performs in different environments, browsers, operating systems with various configurations.

So, It can be concluded that thorough testing helps in successful software development. By identifying the issues early in the Software development life cycle helps in smooth experience for the users.