Postman is an easy-to-use tool and ideal if you are writing your own API. If you are writing a server-side code in a technology like NodeJS, PHP or whatever and you would like to see how it’s working, Postman enables you to immediately interact with your backend and get some feedback on how things are going.
With Postman, you can test different parameters, different authentication methods, setting headers or cookies, or anything that any client-side application can do. All this without writing any frontend code. This doesn’t just speed up the development time, but it allows you to easily find bugs early in the development stage.
Do I Need to Build an API?
You don’t have to build your own API to take advantage of using Postman. Often, we use third-party APIs like Facebook or Google Authentication. With Postman, you can get a sense on how a particular API works by interacting with it.
The longest middle input field that looks something like a search bar is where the URL that we want to GET or POST is fed. In the example above, it's the input box with http://www.demo-url.com?demo_key=demo_value as value
To the left of it, is a dropdown which has all the various HTTP methods as options. The default value is GET
Below is the Params tab where you can set key-value pairs.
To send this request, you click on the blue Send button.
When you send this request, you get a response back. In the example above, we get an HTML response. But you can choose any response type for better readability.
On the left (which says Demo Workspace) is our sidebar. In this example, our workspace is called Demo Workspace, that has a Demo Collection as collection name, and a saved request called Demo Request.
Pros and Cons
Super easy-to-use tool.
Supports all possible HTTP methods
There is an option for importing and exporting of existing work so that you don't have to start from scratch.
Testing APIs can be schedules and automated.
May overwhelm a beginner due to too many options
Not always a guarantee that an API developed in Postman will surely work in browser