Functional testing and non-functional testing are two essential parts of making sure software works well.
Understanding the the terms is important so defining them in simple terms:
Functional testing checks if the software does what it's supposed to do.
Non-functional testing looks at how well it does it.
What constitutes Functional and Non functional tests
Functional testing explained:
Functional testing is a type of software testing that verifies that a piece of software or application functions as expected and meets the specified requirements. It focuses on testing the functionality of the software by providing input and examining the output to ensure that it behaves according to the desired behaviour.
During functional testing, testers typically examine the software's user interface, APIs, databases and other aspects to ensure that they perform as intended. This type of testing does not concern itself with the internal workings of the software but rather focuses on the external behaviour that users will interact with.
Benefits of functional testing to software development
Functional testing is crucial in software development. It ensures that the software works as intended, meeting user needs and business goals. By catching problems early, it saves time and money while improving quality. Functional testing supports modern development practices like agile and DevOps by providing quick feedback. Overall, it's essential for customer satisfaction, compliance, and project success.
What is non-functional testing
Non-functional testing, also known as quality attribute testing or quality of service testing, is a type of software testing that evaluates the performance, reliability, scalability, usability, and other non-functional aspects of a system. Unlike functional testing, which focuses on what the system does, non-functional testing focuses on how well the system performs its functions.
Non-functional testing benefits to software development
Non-functional testing benefits software development in various ways. It ensures software works well under different conditions, enhancing user satisfaction and reliability. By identifying vulnerabilities, it strengthens security and ensures compliance with regulations. Additionally, it supports scalability, usability, and cost savings by catching issues early. Overall, non-functional testing ensures high-quality software, leading to better user experiences and business outcomes.
Examples of Functional and Non Functional Testing
Functional Testing Examples:
login process of an App. (This could be your business or other App)
Login Process
Objective: Ensure that users can log in successfully using valid credentials.
Scenario: Enter a valid username and password and try to log in.
Expected Result: The app should log in the user and display their chat messages or contacts.
Invalid Username:
Objective: Check the app's response when an invalid username is entered.
Scenario: Enter an incorrect username and a valid password, then try to log in.
Expected Result: The app should show an error message indicating that the username is incorrect.
Invalid Password:
Objective: Test how the app handles incorrect passwords.
Scenario: Enter a valid username and an incorrect password, then try to log in.
Expected Result: The app should display an error message indicating that the password is incorrect.
Forgot Password:
Objective: Verify the functionality for resetting a forgotten password.
Scenario: Click on the "Forgot Password" link, enter a valid email address, and submit the request.
Expected Result: The app should send an email with instructions to reset the password to the provided email address.
By testing these scenarios, the process can ensure that its login process works correctly and provides a smooth experience for users trying to access their accounts.
Non-Functional Testing Examples:
registration process of an APP. (This could be your business or other app):
Performance Testing:
Objective: Check how fast the registration works when many people are signing up at once.
Scenario: Try to sign up with different details at the same time with others.
Expected Result: The registration should be quick and error-free, even if many people are signing up at once.
Security Testing:
Objective: Make sure the registration process is safe from hackers.
Scenario: Try to use fake information or harmful code during registration.
Expected Result: The registration should protect against fake info and code attacks, keeping user data safe.
Usability Testing:
Objective: See if signing up is easy and clear.
Scenario: Ask different people to sign up and see if they find it easy.
Expected Result: People should find signing up straightforward, with clear instructions and no confusion.
By testing these areas for the registration process in the App they can ensure it works well, stays secure, and is easy for users to join.
Differences between Functional and Non-Functional Testing based on various aspects:
CRITERIA | FUNCTIONAL TESTING | NON-FUNCTIONAL TESTING |
Definition | Verifies that the software functions according to its specifications, focusing on what the software does. | Evaluates attributes beyond specific functions, such as performance, security, usability, and reliability, focusing on how well the software performs. |
Main Aspects: | Focuses on specific functions or features of the software. | Evaluates attributes like performance, security, usability, and reliability. |
Testing Goals: | Ensures that the software behaves correctly and performs its intended functions. | Ensures that the software performs well under different conditions and meets quality standards beyond basic functionality. |
Testing Methods: | Typically involves black-box testing techniques, focusing on inputs, outputs, and expected behaviour. | involves a variety of testing techniques such as load testing, security testing, usability testing, etc., depending on the specific attribute being evaluated. |
Defects & Errors: | Identifies defects related to specific functions or features not working as expected. | Uncovers errors related to performance bottlenecks, security vulnerabilities, usability issues, etc. |
Role on SDLC: | Integral throughout the software development lifecycle (SDLC), from requirements gathering to post-deployment validation. | Also spans the entire SDLC but may be more prevalent during later stages, especially performance and security testing. |
Testing Costs: | Costs can vary depending on the complexity of functionalities and the extent of testing required. | Often involves additional costs due to the need for specialised tools, resources, and expertise, especially for performance and security testing. |
Zamaqo specialises in testing software to make sure it's high quality and reliable. Experts in both functional and non-functional testing, helping businesses deliver top-notch software. Using advanced techniques, they find and fix issues related to how the software works and its performance, and usability.
In summary, Functional testing ensures that software functions correctly according to its specifications, while Non-Functional testing evaluates other attributes like performance, security, usability, and reliability to ensure overall software quality. Both types of testing play crucial roles in delivering high-quality software products.