What is an API ?

Application Programming Interface is referred to as API. API is a code that enables data interchange and communication between two distinct software programmes. It serves as a link between various software and hardware.

How does an API work?

Here’s how an API works:

1. To obtain information, a client application makes an API request, also referred to as an API call. The Uniform Resource Identifier (URI) of the API is used to handle this request, which comes with a request verb, headers, and occasionally a request body, from an application to the web server.
2. When the API receives a legitimate request, it calls the external application or web server.
3. The server replies to the API with the data that was requested.
4. The API sends the data to the application that made the initial request.

Let’s take an example-

Consider that you are a restaurant patron. Customers like you (the user) and the kitchen are connected by the waiter (the API) (web server). When you give the waiter your order (through an API call), the waiter calls the kitchen to get it. The waiter will finally deliver what you requested.

You and the kitchen are connected through the waiter. The waiter in this metaphor is essentially an abstraction of the API. An abstraction is a fundamental idea in software engineering that seeks to simplify a complicated operation by concentrating only on the specifics that are more crucial. In this case, the food is what the consumer wants, thus they don’t need to understand how the kitchen or the restaurant run. All you need to know is how to place an order.

Why do we need an API

An application programming interface can help you manage current tools or create new ones while streamlining the process. The following are some of the principal advantages of APIs:

• Improved collaboration: You can create and test APIs using collaborative tools for APIs. For groups, they offer resources for API management, documentation, and testing. Without APIs, many businesses would experience information silos and a lack of connectedness that would impair productivity and performance.
• Easier innovation: With the flexibility that APIs provide, businesses can connect with new business partners, provide new services to their current market, and ultimately access new markets that have the potential to produce enormous profits and accelerate digital transformation.
• Data monetization: To attract developers to their brand and cultivate relationships with possible business partners, many firms opt to provide APIs for free, at least initially. However, you can monetize it by selling access if the API provides access to valuable digital content (this is referred to as the API economy).
• Added security: As previously said, APIs add an additional layer of security between your data and a server. By establishing API gateways to monitor and authenticate traffic, employing tokens, signatures, and Transport Layer Security (TLS) encryption, as well as by engaging in effective API management, developers can further increase API security.

1. Public APIs —
   Any outside developer or company may utilise a public API because it is open and accessible. A company will create and provide a public API if it cultivates a business plan that incorporates sharing its applications and data with other companies.
2. Internal APIs —
   Only an internal system exposes these kind of APIs, which are also referred to as private APIs. Instead than being used by customers outside the organisation, these are intended for internal usage.
3. Composite APIs —
   This particular class of APIs integrates various data and services. Utilizing Composite APIs is mostly done to enhance performance, accelerate execution, and enhance listener performance in web interfaces.
4. Partner APIs —
   A partner API is a tool for facilitating business-to-business interactions and is only accessible to carefully chosen and authorised outside developers or API consumers. For instance, a partner API can link the internal customer data system with those outside parties if a company wants to selectively share its customer data with outside CRM firms. No other API use is allowed.

How to create an API?

The six steps needed to create an excellent API are as follows:

Preparation

Before you can begin creating your new API, a few important decisions must be made. You should establish an API style guide, specify the application domain semantics, and choose your API architectural style at this phase of preparation.
The formalisation of these procedures enhances developer experience overall and increases uniformity in businesses with numerous APIs.

Design & Prototype

The API needs to be carved out, and soon. You will define the API’s appearance during this phase, develop its stub implementation, and validate it with all parties engaged in the workflow.

Development

Everything is ready; now build the server! You will create the API implementation during this step in accordance with the API design you created during the design and prototype phase. The API implementation will undergo automatic testing against its design to ensure that it complies with the contract.

Delivery

It’s time to deliver your API implementation to the clients when it has been created, tested, and put in place. There are various methods to introduce your API to users, from handing out the explanation to offering them a gorgeous interactive guide.

Consumption

Your API has now been deployed and implemented. Users of your API do not need to wait for the API to be developed before beginning work on the client. They have a prototype and stub implementation of your API with the Apiary Mock Server, which they can use to create the client.
During this phase, your API users will construct their clients using the resources Apiary offers.

Analysis

The task is never completed. The secret to a successful API is monitoring API usage and paying attention to customer feedback at every stage.