What is an API and My learnings with them

What is an API and My learnings with them

Who should read: Young minds who want to get started with APIs.

Hardik kumar's photo
·

9 min read

Introduction

As a beginner, the term "API" sounded really difficult to me. But today, whenever building a full-fledged application with my team, I always think about what APIs would be needed for the application. I also get annoyed if I don’t get proper documentation of those APIs.

As a beginner, I was able to understand the actual meaning of that term "API" after I integrated it with an application.

But I see plenty of my friends who don’t understand what API actually means. They seem confused while explaining it to me.

But hey.. Don’t you worry! I have got you covered, and will be explaining,

  1. What does API stand for ?

  2. What is need of an API ?

  3. How an actual API looks like?

  4. What is an API key ?

  5. How do we use these APIs in our daily life?

So, let's get started!!


What does API stand for ?

By definition, an API or Application Programming Interface is a connection between two computer programs. In simpler terms, API is a middleman that carries the data between the application and the database.

Let’s understand this line using the most popular example of a customer ordering some food in a restaurant : -

Imagine you’re sitting at a table in a restaurant with a menu of choices to order from. The kitchen is the part of the “system” that will prepare your order. What is missing is the critical link to communicate your order to the kitchen and deliver your food back to your table. That’s where the waiter or API comes in. The waiter is the messenger — or API — that takes your request or order and tells the kitchen — the system — what to do. Then the waiter delivers the response back to you, in this case, it is the food.

In technical terms, API is software that connects the frontend(the web pages that you see and interact with) of any website to its database so that the data on the database could be shown on the website. And also the data on the database could be added, modified, or deleted using the frontend of the website.

Still, there is more to it, let’s understand that in the next part.

What is need of an API ?

An API is needed to connect an application to a database. Here, I used a "database”, which means that APIs can access any database as soon as they have permission to access that database.

Let’s take an example of Amazon, you see a bunch of products on their home page, they have over 12 million products in their own database.

To show a product’s data on their website, they have to make request to the API and get a particular data from the database, then that API sends the requests back to database to provide that particular data. Once response is received, API gives back the same data to the frontend that is being received from the database.

This is how an application connects to its own database. Now talking about connecting with other databases!

Let's take earlier example of e-commerce, which has UPI as one of its payment methods. So what happens here is that the actual payment happens through the company you choose to pay to Amazon. Let’s say you chose PayTM, so you are actually doing a normal UPI payment to Amazon just like you do UPI payment to any other person.

Now for Amazon to check if the transaction has happened or not, it requests PayTM’s API to check if a particular user has paid the required money to Amazon or not Then that API requests the same to PayTM’s database If the database responds with a yes, the API tells Amazon that the user has paid the amount. That’s it!

That’s all the processes that happen behind the scenes. So now that you have better understanding how API connects an application with their own database as well as other companies’ databases too. Let's see how does an API look like.

How an actual API looks like?

There is a public API provided by imgflip that anyone can use in their personal project, I would like you to check it out by yourself.

You see, that is how cluttered it looks in the first place. Let me just show it in a proper JSON format.

JSON(JavaScript Object Notation) is a standard text-based format for representing structured data.

{
  "success": true,
  "data": {
    "memes": [
      {
        "id": "181913649",
        "name": "Drake Hotline Bling",
        "url": "https://i.imgflip.com/30b1gx.jpg",
        "width": 1200,
        "height": 1200,
        "box_count": 2
      },
      {
        "id": "87743020",
        "name": "Two Buttons",
        "url": "https://i.imgflip.com/1g8my4.jpg",
        "width": 600,
        "height": 908,
        "box_count": 3
      },
      {
        "id": "112126428",
        "name": "Distracted Boyfriend",
        "url": "https://i.imgflip.com/1ur9b0.jpg",
        "width": 1200,
        "height": 800,
        "box_count": 3
      },
      ...(more data)
    ]
  }
}

This particular API contains a lot of meme templates that you can display on your own project.

So, this is what all the “API responses” look like whether it’s an API created by Amazon or it’s created by a noob developer like me. It is basically a JSON file hosted online.

And this is what an “API request” looks like:

fetch('https://api.imgflip.com/get_memes')
  .then(response => response.json())
  .then(json => console.log(json))

What is an API key ?

An API key is a unique identifier used to authenticate and authorize requests to an API (Application Programming Interface). It acts as a secret token that the API provider issues to the client (often a developer) to grant access to specific services or data. When a client application makes a request to the API, it includes the API key in the request headers or parameters. The server then validates this key to ensure the request is from an authorized source before processing it. This mechanism helps control and monitor API usage, preventing unauthorized access and tracking how the API is used.

For example, when accessing a weather service API like OpenWeatherMap, you would first register on their platform to receive an API key. Once you have the key, you can include it in your HTTP request to fetch weather data. Here’s a sample code snippet in Python using the requests library:

import requests

api_key = "your_api_key_here"
city = "London"
url = f"http://api.openweathermap.org/data/2.5/weather?q={city}&appid={api_key}"

response = requests.get(url)
if response.status_code == 200:
    weather_data = response.json()
    print(weather_data)
else:
    print("Failed to retrieve data:", response.status_code)

In this example, api_key holds the unique API key issued by OpenWeatherMap, and it is included in the URL as a query parameter (appid). The server validates the key before returning the requested weather data for London.

How to get an API Key?

You can get an API key by registration and account creation on the service provider's website. For example, you start by visiting the site of the API provider, such as Google Cloud, OpenWeatherMap, or Twitter, and creating an account if you do not already have one. After successfully logging in, you would need to navigate to the section of the website dedicated to APIs, which might be labeled "API Documentation," "Developers," or "API Console."

Once you are in the API section, you often need to create a new project or application within the provider’s dashboard. After setting up your project, you look for an option to generate a new API key, typically found under sections like "Credentials," "API Keys," or "Access Tokens." By clicking on this option, you may need to provide additional information such as the name of your project or specific permissions for the key. Once generated, the API key will be displayed, it is important to copy and store this key securely as it will be used in your application to authenticate API requests and won't be visible second time so make sure to store it properly.

How do we use these APIs in our daily life?

There are multiple instance where we do use APIs in our daily life! Let’s start with some common APIs that we all use in our everyday. The most prominent example would be:

a. Login Authentication: - On various websites. You must have seen the buttons saying “Login with Google”, “Login with Facebook”, and “Login with Apple” along with the normal Email and Password login fields.

Login page of Spotify:

They are so convenient to use, isn’t it? They don’t ask for your email or password, you just have to click on it, and boom! you’re authenticated. How cool is that? and who remembers their password anyway. I always go for the “forgot password” option if not with Google, Facebook, or Apple authentication.

So, wherever you see these “Login with XYZ Company”, it means that XYZ Company has provided their APIs to authenticate users through their database.

b. Ecommerce Payments: - If you have ever bought something from any e-commerce website, you’ve definitely seen different options for payment like GPay, PhonePe, and PayTM under the UPI section, right?

Payment options in Flipkart:

So why do you see GPay, PhonePe, and PayTM on all the e-commerce websites while you pay for the product?

It’s because these companies have provided their APIs which the e-commerce companies use to make their payment process simple.

c. Google Map Directions: - Let’s say you’ve ordered something through your food delivery app like Zomato or Swiggy. Now you will be able to see your delivery person’s location, so, how is this happening?

Order tracking page of a Food delivery app:

So the map that you’re watching on your mobile is provided by Google Maps and your food delivery app is asking for your delivery person’s current location from Google Maps. Hence with the help of APIs, Google Maps is able to send that particular data to your mobile.

Conclusion

APIs, or Application Programming Interfaces, are fundamental in today's technology landscape. They act as intermediaries, enabling different software systems to communicate and share data seamlessly. Whether it's for fetching data from a database, handling user authentication, processing payments, or integrating third-party services like Google Maps, APIs play a critical role. As you develop applications, understanding and utilizing APIs efficiently can greatly enhance functionality and user experience. Embracing APIs is crucial for modern application development, making complex processes simpler and more efficient.

FAQs

What does API stand for?

API stands for Application Programming Interface. It is a set of rules that allows different software applications to communicate with each other.

Why do we need APIs in application development?

APIs are needed to facilitate communication between different software systems, allowing applications to access data, services, and functionalities from other systems or databases seamlessly.

How does an API work in a real-world scenario?

An API works by receiving a request from a client (like a web application), processing it by interacting with a database or another system, and then sending back a response with the requested data or confirmation of an action.

What does an API response typically look like?

An API response is usually in JSON format, which is a text-based format for representing structured data. For example, a response from a meme API might include details like the meme's ID, name, URL, width, height, and box count.

Can you give examples of common APIs used in daily life?

Common APIs used daily include:

  • Login Authentication APIs (e.g., Login with Google or Facebook)

  • E-commerce Payment APIs (e.g., GPay, PayTM, PhonePe)

  • Mapping and Navigation APIs (e.g., Google Maps for tracking deliveries) These APIs simplify processes like logging in, making payments, and tracking locations by integrating third-party services into applications.

Resources

If you want to get more gist around APIs, check out trending API tools:

  • Keploy.io — a no-code API testing platform.

  • Hoppscotch.io — an open-source API development ecosystem.

  • Postman.com — an API platform for building and using APIs.

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