What are APIs and How Can You Learn More About Creating and Using Them?

APIs are everywhere these days, and they are the element that underpins a multitude of modern services and solutions.

Getting to grips with the basics of APIs is useful, whether or not you intend to make use of them yourself. But if you’re interested in learning how to harness them, or even what’s involved in creating them from scratch, you’ll need a primer to get you started.

To that end, here’s an accessible introduction to APIs, exploring the ins and outs of what they are, what they do, and how they can be used by you.

Unpicking the meaning of ‘API’

An application programming interface, or API for short, is a conduit for information, allowing one piece of software to request data from a separate system and receive a swift reply.

In simpler terms, it’s a way for applications to interact with one another without the need for more complex integration and cross-compatibility.

An even more relatable way to think about APIs is as waiters in a restaurant. They scurry to and fro, delivering requests from guests to the chef in the kitchen, and returning with what was ordered.

Appreciating where APIs come into play

There are lots of contexts in which APIs are put to work, the most widespread of which is on the web. Apps can use web APIs to make requests of remote servers and retrieve data to present to users as needed.

For example, when you go to sign up to a website, you may be presented with a list of potential login options, including the ability to register for an account using Google or Apple. 

These external services are integrated through APIs, and in this context provide improved convenience for end users, as well as giving the site operator the ability to piggyback on the recognition and trust of better established brands.

Another common place to encounter APIs is when using any application which has location-based capabilities, such as an integrated map. Developers can again tap into a mainstream solution like Google Maps, with the API facilitating this process, rather than having to make their own native map service from scratch.

It’s not just third party APIs that are of interest to developers; plenty of modern businesses choose to create their own in-house APIs to address specific issues that they are facing, or in order to provide access to internal systems and data to third parties.

Understanding API testing automation

When leveraging an external API, it’s necessary to ensure that it is running as expected. If not, it could compromise the user experience of any app or service that you integrate alongside it.

You can test APIs via manual methods, although it is far more efficient to make use of automated API testing. Modern tools and API marketplaces make this straightforward, so you can see whether performance is fit for purpose, or whether response times are less than perfect.

This is just as relevant in the case that you are developing your own API. It should be snappy to respond to requests, or else it won’t serve its purpose or gain traction with external users. By automating testing, you can keep tabs on your API with a much smaller team.

Experiencing APIs as products

APIs are marketable products in their own right, and if you choose to make yours commercially available then you can charge for others to license it and collect fees for the usage it receives.

Likewise if you want to buy into publicly accessible APIs so that they can be integrated with your next app project, you’ll need to consider the costs involved.

Some APIs are entirely open, and neither charge for access nor restrict where and how they are used. Others are premium products, with the aforementioned fees, as well as licensing agreements which specify certain restrictions that third parties must adhere to.

API marketplaces are a good place to find both open and commercial APIs, and in most cases you’ll be able to take premium packages for a test drive to see how they perform and what they can do before you commit to paying for them outright.

Learning about APIs

There are a few ways to get more in-depth information about harnessing APIs, and the aforementioned marketplaces can be a good starting point from this perspective.

You can also turn to the developers of the particular APIs that have caught your interest, and in either case you should be able to take a look at thorough documentation relating to the specific features, functions and integration options of the product in question.

Unfortunately not all API documentation is created equal, and while some examples will be clearly written and include all you need to know, others may be a little light on details, or put together in an impenetrably complex way.

Once again, it’s worth doing your research and testing out APIs before you dedicate yourself to using any particular one.

Likewise, if you are going to create your own APIs in-house, then looking at the documentation that other developers have written will give you a sense of what works, what doesn’t, and what you need to deliver if you intend for your own efforts to gain momentum on the wider market.

Starting your own API journey

In the case that you choose to build an API of your own, it’s a good idea to lay firm foundations before rushing ahead.

Decide what you want the API to do, where you intend for it to be used, and what kind of audience it should appeal to.

Internal APIs tend to be suited best for larger organizations, because of course you won’t be generating licensing revenue from it, but will instead be hoping to recoup your investment in the form of improved productivity.

Public APIs can be a pleasing business proposition, but only if they are equipped with competitive capabilities and are built to take on any rivals in the same niche.

With all this taken into account, you should be ready to take your first tentative steps into the ecosystem of modern APIs.