by Aditya Kapre Shrewsbury Massachussets Boston What Is an API Key? As the name suggests, API keys are simply an authentication password between computer applications. They are widely used anywhere applications are present. If you are wondering, ‘ How do API keys work?’ or ‘ What is an API key?’ , we discuss it all in this article. API Keys: What are they? An API key is a piece of code that acts as a unique identifier of users, developers, and the programs making the API call. Before we discuss what an API key is, let’s first talk about APIs. An Application Programming Interface allows software applications to interact with each other, send and receive data, and share functionality. These connections between internal applications and those integrated for your consumers and business partners help organize and optimize your systems. So, what is an API key? This key is essentially a security protocol that usually takes the form of randomly generated characters to protect your API.