Application programming interface commonly known as API, is basically a protocol or a set of guidelines that allows applications to communicate with other applications. They can even share data and features with each other.
APIs only allow applications to share information that is necessary and keep the rest of the details related to the internal system hidden and secure. It only allows the sharing of small bits of data which is relevant for particular requests.
How Does API Work?
Just assume, API is like a communication channel that connects two parties: the server and the client. Here the client is the application. So whenever the application sends a request for accessing data or features the server responds to it.
Here, the API acts as the bridge that makes it happen which means let them communicate with one another.
Let’s take a simple example to help you understand how APIs work. When you buy something from a website and choose to pay with a third-party system like PayPal, APIs come into play. When you press on the payment button, a request is directly sent to gather the information, which is then processed through the API.
Once the website sends an appropriate request to the API, it reaches out to the server, such as the third-party payment system. The server then sends back a response to the API with the requested data.
Finally, the API transfers this data back to the original application, which, in this case, is the website. This exchange of information happens seamlessly in the background, without the user seeing it.
APIs ensure smooth communication between different applications, making them appear like they are seamlessly connected.
However, you also need to know that there are different types of APIs available in the market, which are:
1. Data APIs
These types of APIs are used for connecting apps or software to database management systems.
2. Operating System APIs
This type of API are local APIs that are used to outline how an application can use operating system resources and services.
3. Remote APIs
These are popular APIs that are commonly used for remote operations. It outlines how apps can interact with different devices.
4. Web APIs
This category of APIs are used to transfer data and features over the internet via HTTP protocol.
Under Web APIs there is again 4 main subcategories:
5. Open APIs
Open APIs are commonly known as public APIs. They are open-source app programming interfaces that can be accessed via HTTP protocol.
6. Partner APIs
Partner APIs are used by developers and they can access these APIs through a special portal (these portals are specially made for developers). But, they need to go through a systemic process first and get permission to use them.
7. Internal APIs
These APIs are kept hidden from people outside the company. These private APIs are only for use within the company.
8. Composite APIs
They are slightly different from other web APIs. They combine different sets of data or services into one. This means that programmers can get all the information they need with just one request.