What are APIs?

Application programming interfaces, or APIs, help make applications and digital services easier to consume. APIs also make it easier for developers to build, enhance, and maintain applications. How exactly? In a nutshell, APIs are specifications that dictate how software components interact with each other, and define how data is shared and modified. Usually written in machine readable formats such as XML or JSON, APIs make it possible to seamlessly transmit data between disparate systems.

What do APIs do?

APIs do two things: first, they allow people to build applications (software) that communicate with existing applications and services. And second, they allow people to build applications that perform certain actions on data. Some APIs even give software the ability to interact with physical devices using specialized protocols.

With APIs, you can build applications that automatically update without requiring any manual work. You also empower users to interact with existing applications and services in a more efficient way. This increases developer productivity by allowing them to focus on the functionality of their application, not on the software components.

Types of APIs

There are different types of APIs, some of which are used for communication between microservices. These types include SOAP, RESTful, and graphQL APIs. Some APIs are intended to manipulate data, such as CRUD (create, read, update, delete) APIs.

APIs vs microservices

APIs and microservices often get confused because microservices use APIs. However, APIs are usually the communication medium between microservices, which are groups of software components that communicate autonomously. Microservices are capable of processing requests on their own, usually without requiring human intervention. Those requests can be for actions such as reading data, updating data, or even deleting data. So again, microservices leverage APIs but are not in fact APIs themselves.

Examples of APIs

A lot of this may sound scientific if you’re not familiar with the terms. With that said, it may be helpful to include a few real-world examples of APIs in the wild. One example is the Twitter API that allows people to build applications that are able to pull Twitter data and compose tweets. Using an API, it’s possible for an application like Tweetbot to pull tweets from a Twitter account, and allow the user to compose a new tweet without ever logging into the Twitter website. Similarly, the API for Gmail allows people to build applications that allow users to compose emails and send them, without ever logging in to the Gmail website.

Why APIs need to be secured

Since APIs make applications and services easier to consume, open APIs make it easier for malicious actors (hackers) to steal data, abuse company resources, and other malicious activities. Therefore, APIs need to be secured. One way is by using authentication mechanisms to ensure that only authorized users (applications and services) can access data. Another way is by using a data encryption mechanism to protect the data from being viewed by unauthorized users.

The truth is, securing APIs requires quite a bit of thought. And traditional application security tools aren’t designed to provide the security controls and observability required to adequately protect APIs. Which means that modern API security solutions are really the only way to secure your API estate. With that said, we encourage you to investigate Noname Security. Our API security platform helps to accurately inventory all APIs, including internal and shadow APIs, and proactively secure your environment from API vulnerabilities, misconfigurations, and design flaws. You can learn more here.