APIs are a term that founders regularly encounter in discussions about software integrations and automation, yet many have only a vague understanding of what they are or how they work. Understanding the basic concept of an API — even without any technical depth — is useful for any founder evaluating software, working with developers, or exploring how their business tools might be connected more effectively.
An API — Application Programming Interface — is a set of rules and protocols that allows different software applications to communicate with each other. When one piece of software exposes an API, it provides a structured way for other software to request data from it or instruct it to perform actions. For example, an accounting application might expose an API that allows a payment platform to automatically push new invoices into it. APIs are the technical mechanism that makes software integrations possible.
Most founders interact with APIs through the integration platforms and no-code tools that use them under the hood. Knowing that a piece of software has an API, and understanding roughly what it enables, is useful when evaluating whether two tools can be connected or when discussing integration possibilities with a developer. Our guide to APIs and software integrations explains the key concepts for non-technical founders.