Difference between Use Case, Test Scenario and Test Case

 What is the difference between Use Case, Test Scenario and Test Case: 

Use Case, Test Scenario, and Test Case are all important components of software development and testing processes, but they serve different purposes and are used at different stages of the project lifecycle.

1. 1. Use Case:

   • A Use Case describes a specific interaction between a user (or actor) and a system to achieve a particular goal or outcome. It outlines the sequence of steps or actions performed by the user and the system's response.
   • Use Cases are typically written in a narrative format and focus on capturing user requirements and behaviors from a functional perspective.
   • They help stakeholders understand the system's behavior in real-world scenarios and serve as a basis for defining system functionalities.
   • Example: A Use Case for an e-commerce application might describe the process of a user searching for a product, adding it to the shopping cart, proceeding to checkout, and making a payment.
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2. 2. Test Scenario:

   • A Test Scenario represents a high-level description of a specific feature or functionality to be tested. It defines the conditions under which testing will be conducted and the expected outcomes.
   • Test Scenarios are broader in scope compared to Test Cases and often encompass multiple Test Cases that cover various aspects of the scenario.
   • They help testers plan their testing efforts by providing an overview of the areas to be tested and the corresponding test cases.
   • Example: A Test Scenario for the e-commerce application might involve testing the checkout process, including scenarios such as successful payment, payment failure, applying discount codes, and handling out-of-stock items.
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3. 3. Test Case:

   • A Test Case is a detailed set of conditions, inputs, actions, and expected outcomes designed to verify specific aspects of the software under test.
   • Test Cases are derived from Test Scenarios and provide step-by-step instructions for executing tests and validating system behavior.
   • They are written in a structured format and include preconditions, test steps, expected results, and actual results.
   • Test Cases are used by testers to perform functional, regression, and other types of testing to ensure the software meets specified requirements and quality standards.
   • Example: A Test Case for the e-commerce application might focus on verifying the functionality of the "Add to Cart" button, including steps to navigate to the product page, click the button, verify the product is added to the cart, and confirm the updated cart contents.

In summary, while Use Cases describe user interactions and system behaviors, Test Scenarios outline high-level testing objectives, and Test Cases provide detailed instructions for executing tests and verifying system functionality. They complement each other in ensuring thorough testing coverage and effective validation of software products.