In a recent article, Forbes.com wrote:

APIs used to be a technical implementation detail reserved for developers and architects. Most executives could hardly spell A-P-I, let alone understand their purpose for programmatic access to software-based products. But that’s quickly changing, as APIs become a primary customer interface for technology-driven products and services and a key channel for driving revenue and brand engagement.

Huh?

An API, or application programming interface is simply a set of rules for which information in a system can be shared, and how that information is sent or received. I’ve written about APIs before. The API most of us are familiar with is an RSS feed. Your website produces a list of articles, along with other pertinent information – date, category, canonical link, etc. This information is always presented in the same way, which is an RSS feed, which is an XML document that specifies a list of syndicated content. If I want to read that list with my program, I don’t have to guess how the data is being formatted, because I already know what to expect. All I need to do is ask your blog for the list in the standard way (in this case fetching a link), and I will get the information I want. More complicated applications will necessarily have more complex APIs. In the reverse, the structure of the data being fetched has to conform to an expected response, otherwise the program won’t understand the resulting data. Remember, computers are stupid.

Simply put, if you need to get information or send information to another website, or provide information from your website, your web developer will probably ask you for the API details. All they’re asking is “how do I talk to the other system?”

Data is the point of any website. Being able to access data to enhance your own website, whether it’s a weather feed, currency exchange, products, database records, or financial transactions is up to your developer and the APIs that let systems exchange data.

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