An Open API, also called a Public API, is a publicly available application programming interface that provides developers with programmatic access to a proprietary software application or web service.
An Open API is like the ordering buttons on a public vending machine.
Restaurants tend to only be open for certain hours during the day. If you try to go to a restaurant after they are closed, you can’t access their waiter to order your food. A public vending machine is open 24/7 and is available to anyone who walks by.
Maybe the vending machine is in the park. You first need to go to the park, and then you can access the vending machine. If there are a lot of people trying to use the vending machine at once, it may be a little slow to place your order, but at any time of the day, you are able to go and press those buttons to get a snack.
An Open API is one that is publicly available to anyone who wants to utilize it.
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 open 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 open APIs.
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 open API is important and why you should or shouldn't care about it if you do not have a product.
As a founder, an Open API is not too relevant if you don't have a product yet. You should learn about the functionality of an API, but the actual type of APIs is more relevant once you actually have a product and need to understand how your site should function most effectively.
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 open API carries a different weight.
As a founder, an Open API is fairly relevant if your business model requires you to interact, via software, with other 3rd parties. For example, if you are Google Calendar, then knowing that your application has an Open API is very important because it is pivotal to your business model to allow other services to pull in calendar information.
So you know what an open 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 open APIs.
In most of your day-to-day, you are likely interacting with many open APIs that you didn't even realize existed. Let's walk through three of the most popular (commonly used) open APIs: