APIs: The BFF of Software Couples

You’ve come across the term ‘API’ many times. We always hear how tremendously helpful it is, and how a lot of companies are using it. Like many people, I didn’t clearly understand what an API was until I had to work with one. In this article, I will therefore explain what APIs are and why you need them, while also giving you an overview of API specifications, documentation, and more.

Table of Contents

• What is an API? A brief introduction.
• How do APIs work?
• Types of APIs
• Why do we need APIs
• Where are APIs used?
• API Documentation
• Conclusion

What is an API? A brief introduction.

API stands for Application Programming Interface. APIs are a set of functions and procedures that allow applications to access data and features from other applications, services, or operating systems.

In simple terms, an API serves as the middleware that lets computer applications or pieces of software interact with each other. The API is not the database or the server, it is the code that governs the access point(s) to the server.

To understand this better, think about booking tickets for a flight or a movie. When you access the website to book the tickets, an API is used to interact with the airline or movie theatre’s database and display the price for the vacant seats.

How do APIs work?

As the name suggests, an API is an ‘interface’, essentially a way to talk to a program.

In simple terms, the API receives a request from the user, which it sends to the server. The server then responds to the request and delivers the desired data to the user.

To understand this better, let’s talk about a very common real-world example: dining at any restaurant.

Whenever you go to a restaurant, you wish to order your desired food from the menu. In this scenario, the restaurant’s chef is the ‘server/data source’ you wish to interact with. Since you cannot talk directly with the chef, you place your order with the help of a waiter, who acts as the link between you and the chef.

Just like the helpful waiter who seamlessly connects you with the kitchen, the API is an interface that takes input data from you and delivers the appropriate response from the application. Check out this short video by Mulesoft for more information on this topic.

Types of APIs

There are three main types of APIs.

1. Private APIs:

As the name suggests, these APIs are not open-source. They are built for use only within their specific organizations. An example of a private API is Home-Cost, a home building cost calculator which is provided as a customized installation for each client.

2. Partner APIs:

Partner APIs are only available to specifically selected and authorized outside developers or API consumers, as a means to facilitate business-to-business (B2B) activities. A suitable example would be the Japanese health technology company Omron’s approach to implementing a partner API model. Omron collects data from e-health medical devices and sells the aggregated datasets to partners, who then use them to provide real-time health data to practitioners. The functions required to access this data are all provided via specific partner APIs, which are only made available to the company’s partners.

3. Public APIs:

Public APIs are open and available for use by any outside developer or business. For example, the Humanitarian Data Exchange (HDX) API is an open-source, public API, which can be used by anyone to interact with the HDX Website.

Why do we need APIs?

Simply put, APIs are efficient and make it easier to access a variety of resources. They allow cross-platform communication and simplify complex problems by tackling different business logic in chunks.

An API can provide the data you need without requiring extra research or manipulation, which significantly speeds up the software development process.

Additionally, APIs make it possible to integrate different systems together, like databases, learning management systems, etc.

Where are APIs used?

APIs have a wide range of applications which include:

1. APIs support most web applications.
2. APIs are the backbone of mobile applications.
3. APIs facilitate desktop applications.
4. APIs help in establishing connections between devices and the internet.
5. APIs connect everyday devices such as wearable technologies, automobiles, sensors, etc.

API Documentation

API documentation is basically a dictionary or reference guide containing instructions on how to use a specific API. It describes the services or functions the API offers, explains how to use them, and aims to cover everything a client would need to know for practical purposes.

In general, API documentation covers the following:

1. A quick start guide
2. Authentication information
3. Explanations for every API call (request)
4. Examples of every request and return with a response description, error messages, etc.
5. Samples of code for popular programmatic languages like Python, Java, JavaScript, etc.
6. Tutorials

Conclusion

As you can see, APIs are a powerful tool that is present almost everywhere.

By providing multiple industries with improvements in speed, agility, consistency, and accuracy, the value of APIs and the potential of extending and integrating application data flows in such a way continues to be recognized by companies. This allows for smoother business process integration across applications, in conjunction with other types of B2B technology.

I hope you found this resource useful and it helps you understand APIs better.