Explain API testing with an example

API testing, or Application Programming Interfaces testing is a kind of software testing that involves verifying and validating APIs and Web services. It’s also a part of integration testing which determines whether the developed APIs meet the tester’s pre-established expectations, such as functionality, reliability, performance, or security. API testing is entirely different from testing. While GUI testing mainly focuses on the functions of an application that are visible to the users, API testing primarily centers on the logic layer of the software architecture。

There is one exmaple that we can relate is booking systems. As we know, like tripadvisor and bookings, which all of them are popular booking system. when we enter the destination, once we select dates and click on search, what you get back are the results from different hotel. These must be some ways that these hotels are acutally exposing some level of information to bookings. That's all API.

                                  What are the different types of non-functional testing?

Non-functional testing is defined as a type of testing to check non-functional aspects of a software application which includes ,usability, reliablity, security

Security testing focuse on how a system is safeguarded against deliberate and sudden attacks from internal and external sources.

Reliabity testing, that means software system continuously perform the specified functions without failure.

Usability :The ease with which the user can learn, operate, prepare inputs and outputs through interaction with a system.

Scalabity:The term refers to the degree in which any software application can expand its processing capacity to meet an increase in demand

                            What is User Acceptance Testing and who does UAT?

It is last process of the software developement. An acceptance test can be understood as a way to check if a previously defined “contract” between the developer and the customer is still on track. Running those acceptance tests also ensures that no requirement change has happened in the meantime and that everything is as it should be to satisfy the customer.

                        What is compatibility testing and how they are performed?

Compatibility Testing is a type of Software testing to check whether your software is capable of running on different hardware, operating systems, applications, network environments or mobile devices.

• The initial phase of compatibility testing is to define the set of environments or platforms the application is expected to work on.
• The tester should have enough knowledge of the platforms/software/hardware to understand the expected application behavior under different configurations.
• The environment needs to be set-up for testing with different platforms, devices, networks to check whether your application runs well under different configurations.
• Report the bugs. Fix the defects. Re-test to confirm defect fixing.

Manual testing is important because it helps demonstrate that required business functions are operating in a manner suited to real-world circumstances and usage.