Application Programmer Interface (API)

Updated: Mon, 18 May 2015 by Rad

Application programmer interfaces offer developers a convenient means to interact with complicated applications in a standardized fashion. Many database platforms support common APIs like Open DataBase Connectivity (ODBC), Java DataBase Connectivity (JDBC) and others.

A good API makes it easier to develop a program by providing all the building blocks. A programmer then puts the blocks together.

There are many different types of APIs for operating systems, applications or for websites. APIs often come in the form of a library that includes specifications for routines, data structures, object classes, and variables.

In other cases, notably SOAP and REST services, an API is simply a specification of remote calls exposed to the API consumers.

An API specification can take many forms, including an International Standard, such as POSIX, vendor documentation, such as the Microsoft Windows API, or the libraries of a programming language, e.g., the Standard Template Library in C++ or the Java APIs.

Virtually all software has to request other software to do some things for it. To accomplish this, the asking program uses a set of standardized requests, called application programming interfaces (API), that have been defined for the program being called upon.

Although APIs provide a quick and easy way to tap into an application, they can be constraining for certain power users such as independent software vendors. Open source code exposes every instruction and operation in an application and therefore offers the most flexibility. Application developers and vendors must constantly be thinking about whether their APIs will be understandable to future developers.

Indeed, many large technology firms, such as Twitter, LinkedIn and Facebook, even allow the use of their service by third parties and competitors.

Some of popular APIs

  • Google Maps API
  • Twitter API

There is also site which tracks popular public API's on the web. Programmable Web, a site that tracks more than 13,000 APIs.

APIs are getting hot with governments

In recent years, we've seen an unprecedented opening of government, and a sustained surge towards transparency. In the UK, we've seen the launch of, which is a 'one-stop shop' of government datasets and statistics, ripe for analysis by statisticians, journalists and data scientists. APIs changed the ways governments operate, and they've brought an unprecedented range of choice when it comes to how you use the Internet.

APIs have a long legacy, but it's fair to say that in 2015, they are accepted as the single most critical ingredient of running a digital business. APIs and the data they manage are already doing incredible things in almost every corner of the business world, and for innovative companies, they provide the key functionality for an entire digital business.

In 2015, we'll start to see APIs move from being an interesting innovation story to becoming the key driver of business strategies

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Application Programmer Interface - from around the web

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