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The History of APIs and How They Impact Your Future

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Interested in the history of API? Read our timeline to see how API has changed throughout the years and what may come in the future.

It’s hard to imagine what the world would be like without APIs, but it’s safe to say that our everyday lives would look very different without this concept at work behind so much of the technology we take for granted.

Below, we’ll delve into API history and look at industry-specific examples of how API integration fuels today’s innovations.History of API Chalkboard-1.jpg

Whether you’re an IT manager, developer or someone simply working in the industry who is curious about this topic, the following will tell you everything you need to know about the history.

What Is An API?

API stands for Application Program Interface. It refers to a set of tools, protocols or routines used for building applications. An API informs software how it must interact.

Another way to understand API is to think of it as the waiter in a restaurant. There’s the user(diner), and there’s also the software(cook). In a restaurant, the diner’s order needs to get to the cook and the result – their actual food – needs to be returned.

When it comes to applications, this job goes to API. It is the connection that makes possible the interaction between people and their devices and the digital systems they rely on.

A quick example you’re probably familiar with is trying to book a flight. Nowadays, most of us use sites like Kayak, Expedia, Travelocity, and Orbitz.

Whatever your preference, they all do the same thing. You tell the site when it is you want to leave, where it is you’re going when you’d like to come back, cabin preferences, budget, etc.

These sites don’t have direct access to the airlines’ databases, though. Instead, they interact with the airlines’ APIs, returning what your options are for that upcoming trip. They essentially go to the airlines with your order and come back with the results. 

In other words, APIs are all about connection, and are a way to integrate data from one source into another source, such as a web service or mobile app. 

Who Invented API?

According to many, the API timeline begins with a man named Roy Fieldings and, more specifically, his Architectural Styles and Design of Network-based Software Architectures dissertation, which he delivered back in 2000.

While it’s true that this probably begins the history of web API, the concept itself was already in over thirty years old by the time Mr. Fielding’s published.

The history of application programming interface really started back in the 60s, far predating the use of personal computers. Typically, an API was used as libraries in operating systems.

API History:

In the 1970s APIs experience their first big leap in progress thanks to distributed systems. Methods emerged that allowed remote access to the procedural API while bypassing the typical programmer overhead through data packing and unpacking required for interoperation between different kinds of computers.

One especially big advancement during this period was Message Oriented Middleware. This addressed the specific needs of Enterprise Application Integration (EAI) by offering bridges to legacy mainframe systems using API integration instead.

The most notable example of this was IBM MQSeries, which introduced proprietary mainframe messaging technologies to the rest of the world.

These message passing and queuing systems tackled many of the problems that had been hindering distributed computing. For example, they ensured delivery of the messages by doing away with point-to-point dependencies.

API History: The 1980s

Another major leap in the history of the API came in the late 80s when Object-Oriented Programming (OOP) transitioned out of academia and became a method by which complex applications could be organized into “objects” which summarized data as well as the procedures that would act on said data.

API History: The 1990s

In the ‘90s, distributed systems became even more common thanks to the introduction of the commercial WWW and client-server topologies that were far more advanced than their predecessors.

Once again in the history of API, we see that the world of OOP played a big role. It was in the 90s that new OOP techniques emerged that allowed remote access to object instances.

Early in the decade, Tim Berners-Lee also introduced the first prototype web browser. This also meant the first HTML page too.

Then, in 1995, JavaScript debuted. At the time, it basically had the same functionality as HTML, but it is still important in terms of the history of API integration because it was a major step toward being able to build client-side assets.

During the late 90s, more and more programmers began taking advantage of the new capabilities made available by the now ubiquitous WWW. They used it for avoiding transport layer management issues, leveraging markup abilities with the parent HTML and much more.

Finally, the history of API and API integration for this decade closed out with Service-Oriented Architecture (SOA). This new architectural style and its standards were created to support the necessary functional granularity and non-functional expediency for distributed computing.

API History: 2000s

As we touched on earlier, this new century began with Roy Fielding publishing a dissertation that is fundamental to understanding the history of APIs. Amongst other qualifications, it’s important to point out that Fielding was an early leader in the development of the WWW and even helped create the HTTP standards that drove its data communication.

During this decade, practitioners realized that the existing model of WWW could be used to counter the awkward and convoluted efforts of the past decade while also taking advantage of its technical infrastructure to replace the bloated middleware that had been used up until this point.

API History: 2010 to Present

We’re currently living in the era of Web API, which started back in 2005. Since 2010, however, the prevalence of public API has soared.

API integration helped make businesses like Amazon and eBay possible has now become commonplace and its popularity doesn’t show any signs of waning.

A History of API Integration Across Specific Industries

Another way of looking at API integration is to focus on the innovation it has brought about. After all, as we just covered, the history of API took small steps until around 2005, after which things began rapidly changing.

There are four major areas we’re going to look at to continue our look at API history:

  • Ecommerce
  • Social Sites
  • The Cloud
  • Mobile

API History: Ecommerce

This is a fairly obvious industry to bring highlight on the subject of the history of API because, as we mentioned earlier, ecommerce was the first commercial beneficiary of this technology. The most obvious examples of this are: 

  • eBay: In 2000, the eBay Application Program Interface was rolled out. It allowed developers to create portals for directly accessing the eBay database. This portal could have its own interface, customized functionality, and specialized operations not otherwise found on eBay.
  • Amazon: Many of us take it for granted now, but back on July 16, 2002, Web Services became a part of not only API history but history in general. The Amazon API allowed developers to incorporate content and features from the popular ecommerce site into their own. This API also allowed other sites to search and display inquiries from Amazon in XML format.

API History: Social Sites

The rise of social media has ushered in unprecedented changes to the way we do just about everything. However, it has also earned an important chapter in our API history lesson.

Let’s now look at two examples of how API impacted this industry.

  • Twitter: On September 20, 2006, the popular social media platform unveiled their Twitter API. Interestingly enough, the release was probably a bit late as developers had already been scraping Twitter for some time or simply creating their own versions of APIs.
  • Facebook: No conversation about social media and innovation would be complete without mentioning the most popular platform of them all. The Facebook API gave developers the ability to access friends, profile information, photos, events, etc.

API History: The Cloud

Cloud computing is growing by leaps and bounds and, even though it may be relatively new to many consumers, it is already a part of the history of API. Once again, Amazon heads our list.

  • Amazon: This is actually a very important moment in API history because it represents a serious innovation. In 2006, the company launched a brand-new web service, something completely different than anything they had done up until that point. Amazon S3 is a storage web service that also makes it possible for developers to access the same storage infrastructure that Amazon uses to run its global network.
  • Amazon: The ecommerce site earns another spot on our API timeline because of Amazon EC2. It was launched six months after the aforementioned API and offered resizable capacity in the cloud which allows developers to create different sized virtual servers within Amazon’s data centers.

API History: Mobile

The introduction of the Apple iPhone 3G in 2009 was a major evolution in the world of mobile technology. It’s also another turning point in the history of API because of the opportunities it developed for mobile companies.

  • Foursquare: Just three months prior to the launch of the 3G, Foursquare introduced itself to the world at SXSW. A big part of its success was due to the Foursquare API which allowed developers to use API integration create their own location-aware applications.
  • Instagram: A great example of the power of API comes from Instagram and, for this reason, it also deserves to be a milestone in the history of API. Just three months after it debuted, Instagram already had a million users. The company refused to release an API. Proving how much developers crave these powerful tools, one simply made his own by reverse-engineering the app. The company would go on to shut it down and launch their own Instagram API.

The Future of APIs

In the very near future, expect API to change in the following three ways.

Greater Business Agility

After reading about the innovations API has already fueled, it should be pretty obvious that these will continue into the future. One way this will happen is with API that is progressively more agile. While the history of API shows that agility is already a major factor, we predict you haven’t seen anything yet.

Companies benefit greatly by continuing to make API available to developers and making them as easy to leverage toward as many goals as possible. Furthermore, as the Instagram example pointed out, if they don’t do this, developers will generally find a way on their own.

Microservices Architecture

For those who may not be familiar with this concept, microservices architecture is a software development method that allows you to make applications as deployable, modular services that all belong to the same suite. These services act independently but communicate through a lightweight mechanism, so they’re still able to accomplish their stated goals.

This will be a major trend in API because, much like with agility, it allows developers more freedom to use API integration for API-related innovation.

Widespread Private and Partner API Integration

The benefit of a private API is that it has the potential to greatly decrease development time and the required resources for integrating internal IT systems, build new ones that maximize productivity and create customer-facing applications that market reach and increase value to existing offerings.

Partner APIs hold great promise because they give the developer(s) greater access to the company. Essentially, in this type of arrangement, interface designers and business managers work with developers on building new applications.

Leveraging Core (legacy) Systems for API Integration

As trends go, “digital transformation” is a big one. With new technologies quickly outpacing and marginalizing older ones, enterprises must find ways to leverage their past investments to meet demands for new digital services. Specialized use cases such as these have brought forth API specialists, such as Open Legacy, that help organizations automatically and quickly create APIs that leverage core systems including their business logic. So, the process of API creation and API integration is becoming more innovative and streamlined.


With all kinds of innovations happening each and every day, it is an exciting era in the history of API. However, keeping up with the changes and knowing how to maximize the benefits can be tricky to understand. Hiring a company like OpenLegacy to help streamline your API integration is one of the quickest, easiest, and most effective ways to ensure you stay up on all the latest trends and maximize the value.

Learn more about how OpenLegacy can help you succeed with your digital transformation initiatives. Download our white paper, How OpenLegacy Tackles Core (Legacy) System Challenges using API Software

Tags: API Integration, API Software

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