When somebody mentions the "API economy," what comes to mind? If no one thing alone surfaces, you're right. The API economy is a whole congress of players, technologies, and influencers, all striving to market and extract value from an approach that's proving to be as transformative as it is risky.
Here are six big categories to be mindful of whenever there's talk of the API economy -- and some of the major players in those categories.
The app people
At the top of the heap are the API-driven apps that have become staples of enterprise technology: Box, Dropbox, Salesforce, GitHub, Slack, Twilio, and many more. What they provide aren't just standalone apps, but composable building blocks -- pieces from which workflows and even entirely new applications can be created. But they're just the tip of a far larger iceberg.
The framework folks
The container creators
One other word most commonly mentioned in the same breath as "APIs" is "microservices," and containers have become a big part of how API-delivering applications are composed.
Docker, the fastest-growing and most-recognized name in this space, not only provides a convenient way to package API-provisioning applications, but is itself highly API-driven -- a way to make the composition of the API-providing applications more programmatic.
Joyent may be best known for being the company most directly associated with supporting Node.js, but it has also invested heavily in creating infrastructures for running containers at scale. The most recent of these, Triton, does away with the VMs normally used as part of the mix of ingredients for running containers, for the sake of greater speed and flexibility. CoreOS also eschews a full system stack in favor of one made out of containers, an approach Red Hat is eyeing as a possible path of development for its own operating system products.
The platform providers
Those in the business of providing enterprise-oriented APIs, or a cloud-hosted framework for the creation of same, also deserve mention. Everyone involved is bringing a different approach to the table.
Some, like IBM's BlueMix and Watson, are providing business-oriented machine intelligence by way of APIs. Others, like Algorithmia (or Amazon's AWS Lambda) are creating dedicated environments for hosting algorithm- and functional-programming-driven APIs. Microsoft, never one to be left out of any enterprise effort, has Azure App Services sporting its own API creation and management tools, too.
The management, monitoring, and toolset people
Building's only half the battle; you also have to manage, maintain, and oversee what you've built. Companies and business models have thus sprung up around providing toolsets for API management.
WSO2 offers an open source API manager for ensuring a given API can keep delivering. 3Scale sells analytics and management tools, and co-sponsors an API search service for discovering public APIs. Apigee, another provider of analytics services for APIs, recently filed for its IPO -- a sign, perhaps, of its confidence in how much of a viable business model there is in API management.
The silent partners
No discussion of the API economy would be complete without some mention of the providers of APIs and data many of us depend on without thinking about it. The United States Government, for instance, has a whole wealth of APIs that can be leveraged. Twitter is another example, as its Firehose has been the source of more than a few business models.
That said, the dangers of becoming too dependent on any API were exposed recently when Twitter elected to change how Firehose could be licensed. Just because something's provided today doesn't mean it'll still be around tomorrow -- an aspect of the API economy enterprises are still grappling with as they build with it and on top of it.
[Edited to clarify that REST is a methodology rather than a protocol.]