Functional Testing and Its 8 Types - A Definitive Guide

In the software development process, software testing particularly functional testing plays a huge role in improving the performance of the software. Besides, testing operation acts as a communication bridge among the software analyst, software developer, and the software testing specialist. Functional testing has multiple types in it.

Here in this article, we are going to discuss the scope, necessity. Also, here we elaborated when and where to perform various functional testing types? Well, before getting in deep let’s brush up with some basics over the functional testing operations.

What is Functional Testing?

Functional testing is one of the testing types of black-box testing used to ensure the quality of the software/product/application meets as per the requirements. Functional testing done upon the software components by feeding the business process data as the testing requirements and the output of the software to the given business process data determine the quality assurance.

Benefits of Functional Testing

• Ensures customers are satisfied with the software performance.
• Ensures software delivered as defect/ bug-free.
• Ensures all the requirements of the software met in the development process.
• Make sure all functions of the software/ product/ applications are working properly.
• Functional testing ensures the software/ product works as per the customer’s requirement and expectation.
• Make sure the application/ software/ product comes with efficient security and safety features.
• Functional testing automatically improves product/ software quality.
• Make sure the risks and loss associated factors of the product/ software/ applications are reduced significantly.

Techniques Used For Functional Testing

The team of testers usually undertakes two techniques (Requirement based and Business Process based) to perform functional testing over the software. Both techniques involve testing on various aspects of the coded program. Both Requirement and Business process testing techniques intend to improve software performance.

Requirement Based Testing: In this technique, the testing team prioritized the presence of risk factors from the given user requirements. Based on the risk factors, the tester performs by executing the important features of the software.

Business Process Based Testing: In this technique, the testing team gathers the complete business process. After gaining the knowledge of the business process thoroughly, the testing team carries the software testing accordingly.

Types of Functional Testing

1. Unit Testing

It is one among the testing types which is mainly used to test the individual components or units of the application/product/software. Meanwhile, a unit can be an individual function, object, method, module, or a procedure of the application/ product/ software.

The ultimate goal of conducting unit testing is to ensure every unit or individual components of the programmed software or application executes as per the given requirement.

Usually, program developers carry this unit testing operation during the development process especially on the coding phase and it is the first level of testing. Unit testing helps developers to fix the bugs or errors of the application/ product/ software in the early stage of the development process.

2. Component Testing

In this type of testing method, all the components of the application/product/software are testing individually and separately. As far as a technical concern, this component testing is referred to as a module and also program testing.

Unlike unit testing, where the developers carry out the testing operation, here testing professionals carry out the component testing operation to check whether all the components are functioning correctly as per the requirements.

Component testing operation carryout by tester’s right after the unit testing. Depending upon the testing levels and requirements, component testing is categorized into two techniques like CTIS (Component Testing in Small) and CTIL (Component Testing in Large).

3. Smoke Testing

Testers usually refer to this smoke testing method as ‘Build Verification Testing’ or as ‘Confidence Testing’ because this smoke testing ensures the stability of the build applications/product/software. Besides, the ultimate goal of conducting smoke testing is to confirm the Quality Assurance team to carry out remaining testing operations.

In simple words, we can define this smoke testing as a testing operation that ensures the build products/ applications/ software is fully ready to do a testing operation. In general, testers carry out smoke testing whenever they develop and integrate new functions/ modules to the application/ software/ product and to ensure all the essential functionalities of the applications are working as per the requirements.

4. Integration Testing

It is a testing method, where individual components of the application/ product/ software are tested by combining those together. The ultimate goal of conducting this integration testing is to check whether all those interactions between the components are carried out without any faults.

Usually, testers refer to these testing methods as ‘I & T Testing’ (Integration and Testing), ‘String Testing’, and even as ‘Thread Testing’.

This Integration testing is a second-level of testing which is done in-between the unit testing and the system testing methods. Both product developers and also the independent testers can carry out this integration testing method. A professional tester conducts this integration testing in two approaches Big Bang Approach or Incremental Approach.

Meanwhile, an Incremental approach further divided into 3 as Top-Down Approach, Bottom-Up Approach, and Sandwich Approach (which is the combination of the other two approaches).

5. Regression Testing

This testing type is used by the professionals to check whether the software/ product/ application witnessed any changes in its functionality after making changes in the programming codes. In this regression testing, professionals ensure the new functionality of the product along with the exciting features of the products works fine without any mess.

Moreover, to check the impact of code changes professionals usually execute the same test case scenarios done before the code change.

In simple words, this regression testing can be referred to as verification testing where the same test cases are executed again and again to cross-check. Owing to that, conducting regression testing is a tedious and time-consuming one.

6. Sanity Testing

In the testing world, sanity testing and smoke testing are mostly confused since they resemble almost similar to each other’s operations.

However, if we look deep you can find out a significant amount of difference among the literature of both testing methods. The professional carries out this sanity testing operation after the product/ application/ software build with small changes in the codes or functionality to check whether the bug spotted before has been rectified correctly and to cross-check whether any new errors occurred after those changes.

Just like smoke testing, the sanity testing method works with the ultimate goal of checking all the functionality works as per the exact requirements.

7. System Testing

System testing is a type where professional tester tests the software/application/product with the end-to-end system specification after integrating all the modules or components. Generally, this system testing operations are performed by the individual testers who haven’t been involved in the coding/development process of the product.

Unlike other testing methods, this system testing consists of a series of tests in order to ensure the product/ application/ software compliance with the client’s requirements. Moreover, system testing plays a vital role in the validation of the entire applications/software/product meets with the technical, functional, and with the business process requirements of the clients. It is the testing process done right before the product/ software/ application is introduced in the market.

8. User Acceptance Testing

User Acceptance Testing (UAT) is a testing method that is usually carried out at the final stage. Unlike all other testing methods, this UAT is carried out by the end-users or by the client. After this testing process, the software product/application moves to the production environment for more productivity or moves to the market and reaches end-users.

The ultimate goal of conducting this User Acceptance Testing (UAT) process is to validate the end-to-end business flow without any mess. UAT is usually carried in a separate environment where the product tested by the two or more end-users/clients.

Bottom Line

After analyzing all those functional testing types and their importance, we can conclude that functional testing plays a vital role in the client’s awareness of the consumer’s needs and develops the applications accordingly.

Performing all those above-mentioned functional testing types in software testing at the right time of the software development process will ensure delivering quality products. You can know more about our software testing services here.

Frequently Answered Questions on Functional Testing Types

1. Why do Functional Testing?

Functional testing ensures no glitches on your software. By doing so, functional testing avoids your brand getting viral in the wrong way because of the embarrassing software glitches.

2. Is there any best tool to do functional testing accurately?

In today’s market, you can easily find a wide range of open-source testing tools. However, here we have listed a few best testing tools where you can perform functional testing on your software at easy.

• Selenium
• Katalon Studio
• UFT(Unified Functional Testing )
• TestComplete
• Watir
• Ranorex
• Robot framework

3. What are all the tests you can do under functional testing?

Though the prime objective of the functional testing is to test the functional ability of the software program, it does carry various testing operations which are listed below.

• Mainline Functions
• Basic Usability
• Accessibility
• Error conditions, and so.

4. Whether we use manual and automated tools for doing functional testing?

Yes! The tester can use manual or automated tools for doing functional testing according to the specification provided by the client.