Why are they so popular ?
Effortless Integration
Allows partners and customers to access your system in a safe way.
Cloud Computing
is dramatically on the rise. API's are needed for both the initial migration and integration with other systems.
Competitive Market
The market is not so competitive that a company;s success may depend on how usuable and intutitive their API is.
Mobile Phones
and devices embedded with sensors fit the service based structure of API's perfectly
Flexibility
APIs allow you to quickly leverage and use your desired services. This lowers risks and allows gor greater innovation.
Proven success
Companies that adopted and API-first strategy caused disruption of entire sectors and left larger incumbents scrambling to catch up.
How do APIs work ?
API software lets the components of two applications talk to each other using a set of simple commands. Essentially, APIs are messengers that deliver requests and return responses between applications. In each interaction, there's a server (the app providing the resource) and a client (the app making a request). If the server can do what the client has asked, then the API will return the relevant resource. If the client requests a resource that doesn't exist on the server or that the client doesn't have permission to access, the API will instead provide an error message. By only providing data that has been made available to external users, APIs enforce selective access control to the server. Online booking services that aggregate a number of databases show this dynamic in action. Skyscanner, for instance, interacts with each airline’s API interface to request booking information, like ticket prices and baggage options, without requiring you to know how to connect: the API takes Skyscanner’s request to each airline and returns the relevant data in response.
Most common API commands
Most API users want the server to perform basic functions. The four main kinds of API requests are: GET : To retrieve data PUT : To update existing data DELETE : To delete existing data POST : To do everything else, including creating new data Web APIs generally use HTTP to transmit these request messages, which provides a structure for communications between the server and client. While request messages are typically written as URLs, response messages often take the form of JavaScript Object Notation (JSON) files.
Main types of API
Private/Internal APIs are only available internally within an organization. While developers working for the company can use these APIs, third-party developers cannot. As these APIs aren't documented in publicly accessible software development kits, they're often completely unknown to the public.
Partner APIs are shared externally with business partners of the organization. Usually these are used for creating deep integrations , functionality, or accomplishing things that each organization could not individually.