API stands for Application Programming Interface. It may sound like something out of a glossary
of technical terms. Even if you don’t know what it exactly means and how it works, you are
unconsciously using it in everyday life.
You track the live location of a delivery partner carrying your favorite snack for your midnight
cravings with Google Maps on an app. You log in with Facebook or Google credentials to save
yourself the hassles of creating an account on each platform. In all these everyday activities,
APIs are working in the background.
So what exactly is an API, How does it make our lives easier
API provides applications with a standardized way to communicate with each other and
exchange information. APIs will act as the messenger to deliver requests and responses between both ends. APIs will return an error message if the resource requested by the user does not exist or is inaccessible.
What are the characteristics of API
Introduced as a generic connectivity interface, APIs have come a long way in the information technology sector.
● Internet standards like HTTP and REST adhere to modern APIs making them
comprehensive and accessible to users
● Since it is basically software, it has its own software development cycle (SLDC)
● APIs unify many processes to speed up the operations for better a user experience
● APIs support pagination feature to deal efficiently with large data records
What are the types of API
APIs can be categorized into three types based on the availability and release policies:
1. Private/Internal APIs
They are mostly used within the organization as they are typically developed for
the employees to be used in the in-house applications or tools.
2. Partner APIs
They are only aimed at business partners and customers or clients will be
the end-users. They are often used for software integration between two organizations.
3. Public/External/Open APIs
These APIs are typically developed for the public and will be available to any third-party developer. They have the most accessible release policy and can be further
categorized as Open APIs and Commercial APIs.
4. Composite APIs
It combines different data and services to improve the overall performance and
execution process. It can execute a series of requests in a single call.
What is an API call
It is the process of submitting a request to the server's API from the client to retrieve
information. As applications communicate with each other in the background, the process will
seem instantaneous for the user.
What is an API key
It is a unique identifier used to authenticate calls to the other end. They are made up of unique strings and numbers that help in ensuring that the servers’ resources are used only by a specific
set of clients.
Still confused about how APIs work? Let us put all these terminologies to use in a real-world
scenario.
Imagine walking inside a movie theater to buy tickets in which you will represent the customer, the theater will be the server, and the ticket counter will be the API. You need a ticket to watch a movie and your interaction with the server-side begins and ends at the ticket counter.
Typically you will pay at the ticket counter and get the ticket to enter the screen. You will not get to see
exactly how the theater benefits from your money and how the share is divided between the
stakeholders for mutual benefit.
However, if there are issues with the seating capacity due to the enormous crowd, you will have
to reserve the tickets earlier and will get an exclusive QR code. This QR code will be exclusive
to you and can be compared to an API key.
As the theater (client) provided an exclusive QR
code (API key) to every customer, they will not be facing issues with handling the crowd
(incoming resources).
What are the benefits of APIs for businesses
● They are highly valuable to increase user engagement and functionality
● They help speed up the process
● They can be easily modified based on the requirements rather than writing the entire
code
● They can be developed easily as the team will not be starting from scratch
How do APIs benefit the users
● By speeding up the process, they improve the productivity of users
● The functionalities can improve user engagement and end-user satisfaction
● Bridges the gap between multiple applications by seamless integration
Now that you have a vague idea of APIs and their benefits, let us take a look at their
applications
What are the applications of API
● Data sharing
● Embedded content
● Internal system access
● Application integrations
Despite having so many benefits and functionalities, APIs have a set of cons to keep the developers on their feet.
What are the cons of APIs
● APIs will not provide efficient protection against threats as a gateway.
● If an API is breached, other apps will also be vulnerable to attacks.
● Although they are easy to develop, they are complicated to manage in the long term.
● Require a high level of expertise to handle.
● Cannot be expected to be stable in every scenario.
Now that you have a clear view of APIs, let us move on to some of the popular APIs in the real
world and where they are being used.
Some popular APIs in the world
Twitter APIs
Twitter offers APIs that can help to dive into its deep archives, opening up a ton of
possibilities for the applications. It is up to the development team to harness the potential of
APIs in the global communication sector to optimize the application for a better user experience.
Instagram APIs
The recent updates pushed by Instagram are helping businesses to reach out to
customers in a whole new way. Applications enable customers to plug into the Instagram
account effortlessly to share its user-generated content for various purposes.
Google Maps APIs
Google Maps API is a must-have for businesses that have location-based apps. The
integration of Google Maps APIs has taken the on-demand service industry to a whole new
level. With the high level of functionality offered by the API, businesses are able to operate
hassle-free.
Now let us have a brief look at making an API call as a step-by-step process.
How to make API calls
Step 1
Find the URL of the server or external program from which the data will be accessed.
Step 2
Add a request verb to formulate the API request.
Here are the basic request verbs:
➔ GET - To retrieve a resource from the server
➔ PUT - To retrieve or edit an existing resource
➔ DELETE - To erase a resource
➔ POST - To create a resource (new)
After adding the request verb, the request will look something like this. This is an example of a request for seating availability in a movie theater.
GET
https://api.bookmyshow.com/api/alt-seats-availability/v1/nearest.json?api_key=XXXXXXXXX&lo
cation=Chennai
Step 3
Include a header in your API request
There are three types of headers - Content type, user agent, and accept. It helps the API to
understand the request and responds in a way that’s easy to understand.
Step 4
Include an API key with your API request
Step 5
Wait for a response from the server-side
You will get a status code based on the status of your request.
Why should you test API calls
As there will be many APIs, testing API calls is important to get an overall idea about their
performance, vulnerability, reliability, performance, etc. It consists of making API calls to get
various responses from multiple endpoints and will be usually done with a software or web
service.
How safe are APIs
Security is a primary concern on the internet as it involves user data, company reputation, and
more. APIs are prone to vulnerabilities such as issues with authorization, broken authentication,
code injection, etc. Organizations have a separate team to regularly test APIs and identify the
potential threats in them. By following these practices, APIs can be secured from threats.
What is the future of APIs
Somewhere down the line, the emergence of APIs has given rise to a full-fledged business
economy. Initially started as a support for backend operations, APIs are set to become an
extension to the business process to perform heavy-duty stuff. With its potential to automate tasks, APIs are set to define a new future with Web 3.0.
Conclusion
While we have covered the basics of APIs, there’s so much to learn about them. If you are
interested in learning the application programming interface, take a look at these resources on Linkedin.