What is an API?
An API, or Application Programming Interface, is a set of rules and protocols that allows different software applications to communicate and share information with each other.
An API acts as an intermediary or a messenger, enabling one piece of software to request services or data from another. It defines the proper way for a developer to make a request and what kind of response to expect. You don’t see the API, but you interact with its results constantly. When a travel website shows you flights from multiple airlines on one page, it’s using APIs to request that information from each airline’s system in real-time.
In the context of artificial intelligence, APIs are what make it possible to integrate the power of a large language model into other tools. Companies like OpenAI (the makers of ChatGPT) provide an API that allows developers to “call” their powerful AI model from within their own websites, apps, or business software. This is why you see AI features appearing in everything from your word processor to your email client.
Think of it this way: An API is like a waiter in a restaurant. You (the user in an app) don’t go directly into the kitchen (the complex AI model) to get your food. Instead, you give your order to the waiter (the API). The waiter knows exactly how to talk to the kitchen, places the order correctly, and then brings the finished dish (the AI’s response) back to your table. The API handles all the communication so you don’t have to.
Why It Matters for You
As a small business owner, understanding what an API is helps you see the vast potential of AI beyond just the ChatGPT website. It explains how all the new AI-powered tools you’re seeing work “under the hood.” When you use an accounting software that now offers AI-powered expense categorization, or an email marketing tool that can help you write subject lines, it’s because they have used an API to connect to a powerful model like GPT-4. Knowing this helps you evaluate new software and understand how you can start to automate more powerful, integrated workflows in your business.
Example: Automating Customer Service
You want to automatically categorize incoming customer support emails.
- Weak (No API): You manually read every email and assign it to a category like “Sales Inquiry,” “Technical Support,” or “Billing Question.” This takes up a significant part of your day.
- Strong (Using an API): You use a helpdesk tool like Zapier that connects your email inbox to the OpenAI API. You set up a rule: when a new email arrives, its content is sent to the AI via the API with the request, “Categorize this email into one of the following: Sales, Technical, Billing.” The AI’s response is sent back, and the email is automatically tagged and sorted, no manual work required.
Key Takeaways
- An API allows different software applications to talk to each other.
- It’s the technology that lets developers integrate powerful AI into their own apps.
- APIs are the engine behind the explosion of AI features in the software you already use.
- Understanding APIs helps you see new opportunities for automation in your business.
Go Deeper
- Learn More: An API is what allows an application to access a Large Language Model (LLM).
- Related Term: The cost of making a call through an AI API is measured in Tokens.