What is an API?


an API (Application Programming Interface) is a set of functions and procedures allowing the creation of applications that access the features or data of an operating system, application, or other service.


An API is like a waiter in a restaurant.

Imagine that you are sitting down in a restaurant. You are representing the end user. The kitchen that prepares your food is representing the backend. The waiter is who communicates between the two, just like an API.

When you enter the restaurant, you interact with the waiter and place your order. The waiter then walks over to the kitchen and tells them what they need to prepare. Once ready, the waiter will bring your order from the kitchen back to you.

In other words...

An API is what helps facilitate communication between two applications, whether that be the frontend and backend or the backend or your platform and a 3rd party's services.

Why is an API important?

It's one thing to know what a term means, but that is worthless if you don't know why you should know what an API is in the first place. Let's break down the importance of this tech term based on two high level categories. We'll walk through an explanation as well as provide a score, 1-10, that shows you how much you should care about APIs.

Pre-Product: 5/10

The first will be if you do not have a product yet. This means that you don't have a physical product. Maybe you're in the ideation phase, or maybe you're almost ready to start development. Whichever it is, we'll get into why an API is important and why you should or shouldn't care about it if you do not have a product.

As a founder, an API is only relevant to you from a planning perspective. You need to know what third parties you will integrate or communicate with. If you are a product that works with Spotify, you need to read through Spotify's API permissions to ensure that you can actually do what you intend on doing.

Live Product: 7/10

The second category is if you do have a live product. Maybe you just launched your business or maybe it's been live for years and you're continuing to improve its quality. Regardless of the scenario, if your product is live, an API carries a different weight.

As a founder, an API is very relevant to you. You need to know what your product is interacting with. For example:

  • If your app interacts with Google Calendar, you need to understand how it interacts and what data you are trying to access.
  • You need to be able to speak with your developers to make sure your business priorities align with what is possible from an API point of view. If Google changes it's permissions, that isn't in the control of your development team, so you need to pivot as a business.

Examples of APIs

So you know what an API is, by definition. You know if you should care about it or not depending on your situation as a business/company/product. To dig in deeper, we will walk through some examples so we can make sure you really have a solid grasp on APIs.

Three examples of commonly used APIs:

Let's walk through three examples of APIs that you commonly interact with. Some of these you engage with on a daily basis, where as others are more as needed. Whether you knew it or not, these APIs help fuel your efficiency.

  1. Login via Facebook, Google, Twitter, etc.

    When you are logging into an application and the login screen prompts you with an option to login via your Facebook account, Gmail account, Twitter account, or some other account other than your email address/phone number, this is leveraging the API of that third party. To login with your Gmail, the website is accessing Google's API to allow you to validate your identification via Google. To login via Facebook, the website is accessing Facebook's API to validate your identification via Facebook. The API being used allows the site you are on and the site you are using to login with to communicate with one another, making your login experience a whole lot easier as it eliminates needing to know additional usernames and passwords!
  2. Paying with PayPal

    Have you every gone to purchase an item online and you see a little widget that allows you to pay for your purchase with PayPal? That widget is powered by an API. The e-commerce site you are on is leverage PayPal's API to allow you to simply click a button and access your relevant payment information in order to make your purchase. Rather than having to type in account numbers and other validating information, all you have to do is click the button, login, and the API is able to communicate to the e-commerce site the proper information needed to allow you to pay with ease.
  3. Travel Booking

    It's vacation season and you're looking for a cheap destination to travel to. You go to vacation aggregation sites like Kayak or Trivago. As you go on these sites, you see that they are populating the information of hotel and flight prices. They are able to gather these prices immediately due to the APIs that they are accessing. The Kayak's of the world will leverage different company APIs, such as American Airlines, in order to populate their site with all American Airlines' flight information so you can make the most informed decision and shop-around without having to leave their site.

Key Takeaways:

  1. An API is what helps facilitate communication between two applications, whether that be the frontend and backend or the backend or your platform and a 3rd party's services.
  2. If you don't have a product, be sure to plan ahead as to whether you will need to leverage APIs.
  3. If you do have a product, you should understand what APIs you are using.

  4. APIs will allow you to access another company's information, strengthening your user's experience.
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