What is Functional Testing? Types & Examples

 What is Functional Testing?

 It is used to test the functionality of software application whether the function is working according to the   requirement specification. It involves testing the functions, features, and behavior of the system as well   as a whole, ensuring that it performs the intended tasks correctly.

Functional testing lies in its emphasis on testing the application from the perspective of an end user. It is concerned with testing the software's ability to perform its intended functions and deliver the expected results, typically based on the requirements and specifications provided.

Functional testing aims to validate various aspects of the system, such as:

1. Input/Output: It verifies that the system accepts valid inputs and produce the expected outputs.
2. User Interface: It checks the usability and responsiveness of the user interface elements, ensuring they function as intended.
3. Business Logic: It examines the underlying business rules and processes to validate their correctness and integrity.
4. Integration: It tests the interactions, between different system components, ensuring they work together seamlessly.
5. Data Integrity: It verifies the accuracy and consistency of data handling within the system.
6. Error Handling: It ensures that the system handles exceptions, errors, and invalid inputs gracefully, providing appropriate error message or fallback mechanism.

Types Of Functional Testing

• Behavioral Testing: It is used to verify the flow, structures, and design of application according to the requirements specification. For Example: Suppose we are using Flipkart website in that we saw sliders not working, so we use Behavioral Testing for testing.

• Input Domain Coverage Testing: It is used to verify the values adding on input box is valid or invalid values as per requirement specification. It is also used to test the length of the input values in an application. For Example, We input the mobile number and there is only 10 digits to be required and value should be numeric only. So, if we input right values on input box it will be valid or if not, errors will be display.

• Error Handling Coverage Testing: It is used to verify that the values we are adding in input box it displays errors according to the requirement specification. It is also used to test the errors in run time from the application. For Example, we input the email address in application login form but, we put wrong email address on application login form and now it displays an error invalid email address we had enter.

• Backend coverage testing:  It is used to test the data we add on application is saved on database server or not. It is also used to test the server side or database of software. For Example, we login the application and its username and password should be in Database Server.

• Service Level Coverage Testing: It is also known as end-to-end testing. It is used to test the application in a Sequential flow. For Example, if we have to buy a product, book a train ticket, order the food so there should be step by step process.

• Calculation Based Coverage Testing:  It is used to test the calculation as per the requirements by software or application. For Example: We went to a Restaurant, and we pay the bill but in that calculation is done wrong way for that we use Calculation based Coverage testing.