API (Application Programming Interface software) is a set of instructions, standards or requirements that enables a software or app to employ features/services of another app, platform or device for better services. In short, it’s something that lets apps communicate with each other.
For example, when we hit the ‘Connect Facebook’ button on Candy Crush, it does not ask us to enter our Facebook account details. Rather, it accesses the data from the Facebook server and lets us enjoy playing – all thanks to API.
An API is the base of all the apps that deal with data or enable communication between two products or services. It empowers a mobile application or platform to share its data with other apps/platforms and ease the user experience without involving the developers . On the top of it, APIs eliminate the need to build a similar program or platform from scratch; you can use the existing one or some other app/platform. Because of these factors, both app developers and business leaders focus on the API development process.
Terminologies of API development
a) API Key: When an API request through a header or parameter to recognize the requester, the authorized code passed into the request is said to be an API Key.
b) Endpoint: When an API interacts with another system, one end of the communication channel is termed as Endpoint.
d) GET: The RESTful application program interface’s HTTP method of obtaining resources is called GET.
e) POST: It is the RESTful API’s HTTP method for building resources.
f) OAuth: It is basically an Open standard authorization framework that renders access from the user’s side without directly sharing the credentials.
g) REST: REST (Representational State Transfer) is a kind of programming architectural implementation meant to enhance the efficiency of communication between the two devices/systems. It is light-weighted and based on the idea of making a particular data available only when requested by sharing references to the data instead of the entire copy of the data itself. The systems enforced on this architecture are said to be ‘RESTful’ systems, and the most overwhelming example of RESTful systems is the World Wide Web.
h) SOAP: SOAP or Simple Object Access Protocol is a messaging protocol for sharing structured information in the execution of web services in computer networks. It works with XML information set and application layer protocols (like HTTP and SMTP) for message format and message negotiation & transmission, respectively.
i) Latency: Latency is defined as the total time taken by API interface in the process from the request to the response.
j) Rate-Limiting: The term API Rate-limiting refers to the process of defining the rate at which an end user can access the APIs. In other words, it means restricting the number of requests a user can hit to an API per time.
k) API Throttling: The process of regulating the usage of APIs by users during a particular time period is called Throttling. This can be used for API limiting. For example, you set the limit of 1000 API requests per day. When the user hit the 1001 request, the server will send 429 messages as HTTP status to the end user along with the message, “Too many Requests”.
Now, as you now know what is API development and are familiar with terminologies associated with API development let’s dig deeper into the technical part – beginning with how API works and how to develop API (how to create an API)?