1.Functional Testing

This type of testing focuses on ensuring that the API functions as intended. It includes various subtypes:

Smoke Testing: A quick test to check if the basic functionalities of the API are working properly. For example, sending a request and verifying a successful response.
Functional Testing: Thoroughly testing the API endpoints and their expected behaviour. For example, verifying input validation, error handling, and response accuracy.
Integration Testing: Testing the API's interaction with other systems or components to ensure smooth integration.
Regression Testing: Testing to ensure that changes or updates to the API do not break existing functionality.

2.Performance Testing

This type of testing assesses the performance and scalability of the API under different load conditions. It includes:

Load Testing: Evaluating the API's performance under expected or simulated user loads. For example, sending multiple requests simultaneously to test response times.
Stress Testing: Testing the API's behaviour under extreme conditions, such as high traffic or data volume, to identify its breaking point.

This type of testing focuses on identifying vulnerabilities and ensuring the API's security. It includes:

Security Testing: Assessing the API for potential security risks, such as unauthorized access, injection attacks, or data breaches.

This type of testing evaluates the API's user interface elements and their functionality. It includes:

UI Testing: Verifying the API's user interface components, such as headers, forms, buttons, and navigation.

Sending unexpected or random inputs to the API to uncover vulnerabilities or crashes.