A real example of an API

How are APIs used in the real world? Here’s a very common scenario of the API economy at work: booking a flight.

When you search for flights online, you have a menu of options to choose from. You choose a departure city and date, a return city and date, cabin class, and other variables like your meal, your seat, or baggage requests.

To book your flight, you need to interact with the airline’s website to access the airline’s database to see if any seats are available on those dates, and what the cost might be based on the date, flight time, route popularity, etc.

You need access to that information from the airline’s database, whether you’re interacting with it from the website or an online travel service that aggregates information from multiple airlines. Alternatively, you might be accessing the information from a mobile phone. In any case, you need to get the information, and so the application must interact with the airline’s API, giving it access to the airline’s data.

The API is the interface that, like your helpful waiter, runs and delivers the data from the application you’re using to the airline’s systems over the Internet. It also then takes the airline’s response to your request and delivers right back to the travel application you’re using. Moreover, through each step of the process, it facilitates the interaction between the application and the airline’s systems – from seat selection to payment and booking.

APIs do the same for all interactions between applications, data, and devices. They allow the transmission of data from system to system, creating a connected experience. APIs provide a standard way of accessing any application data, or device, whether it’s accessing cloud applications like Salesforce, or shopping from your mobile phone.