An API is simply a way for two different software programs to talk to each other and exchange information. It’s the connection that lets one program ask another program for something and get an answer back.
You use APIs all day without seeing them (and honestly you don’t need to see them).
For example, you ask your AI tool of choice, like ChatGPT, to draft a presentation outline. Then you click Export to PowerPoint or Send to Slides. Depending on the AI tool, you might also receive that outline as a Markdown file, a simple text-based file format commonly used for moving AI-generated content between tools.
A few seconds later, poof, the outline appears in Microsoft PowerPoint. An API allows these two different programs, owned and operated by different companies, to work together.
The button is what you see. The API does all the magic behind the scenes.
That same basic exchange happens whenever you:
Export an AI outline to PowerPoint
Drop a stock photo onto a slide from an add-in
Generate a meeting link
Process a payment
APIs are all around you, and you use them every single day without realizing it. In every case, one piece of software is asking another piece of software for information or help.
What is an API?
An API, or application programming interface, is a defined way for one software program to request information or actions from another.
In plain English, APIs let the tools you already use work together.
Major technology companies like Google, Microsoft, and OpenAI design their ecosystems around APIs because they provide a secure, standardized way to integrate tools. According to software industry standards, APIs are essential because they allow third-party applications to interact with a core system without exposing the underlying source code or compromising security.
Here is a real example using Google Calendar and Zoom.
1. Connecting the two tools
Before Google Calendar can ask Zoom to create a meeting, you first need to install the Zoom app.
2. Review and approve the API permissions
Next, Google asks you to review what the Zoom app will be allowed to access.
3. Use the connection inside of Google drive (in this case)
Once the app is installed and authorized, a new button appears inside Google Calendar:
Make it a Zoom Meeting
Need to see all the steps to hook up Zoom inside of Google caledenar (and not just the final API permission steps)?
See Santa Clara University's guide for setting up this zoom feature inside of Google Calendar for all the steps.
So what's actually happening back there?
Here’s the part that makes APIs click.
An API gives one program a defined way to ask another program for information or to request an action. It spells out what requests are available, how to make them, and what the other program will send back.
The company that creates the API controls those choices.
A weather service might let another program request today’s forecast for Chicago. It won’t let that program request private customer information. A photo library might let a PowerPoint add-in search for images, but not change the library’s billing details.
The API creates a controlled connection between the two programs.
That’s why APIs come up so often now that AI tools are everywhere. When an AI searches your files, a slide add-in pulls from a photo library, or a dashboard retrieves live numbers, an API often handles the exchange behind the scenes.
An API is a set of rules that tells one program what it can ask another program to do, and how to make that request.
You don’t need to build an API, read its code, or install anything to benefit from understanding what one is.
You only need to recognize what’s happening: one program is requesting information or an action from another, using a connection designed for that purpose. Building the connection is somebody else’s job.
Two terms you’ll hear next to “API”
Once you understand APIs, two related terms become much easier.
API key
An API key is a secret credential that identifies the app, account, or project making an API request. The service uses it to decide whether to accept the request and to track usage.
Think of it as an ID badge for software. It identifies the source of the request, which isn’t always the same as identifying you personally.
At some point, an app may ask you to paste in an API key. That doesn’t mean you need to understand code. It usually means the app needs permission to use another company’s service.
MCP
MCP stands for Model Context Protocol. It is an open standard that gives AI applications a consistent way to connect to outside tools and data.
APIs are the broader way software programs communicate. MCP is designed specifically for AI applications, giving them a standard way to discover and use external information and capabilities. An MCP connection may rely on one or more APIs underneath.
In Claude, you’ll commonly see these connections called Connectors. In ChatGPT, OpenAI now generally calls them Apps, although some workspace settings still use Apps & Connectors. An App or Connector may be powered by MCP, but the terms are not interchangeable.
How API, API key, and MCP fit together
API (Application Programming Interface): The foundational set of rules and communication protocols that allows two software programs to interact and exchange data.
API Key: A unique alphanumeric security token used to authenticate and identify the user, application, or project making the API request.
MCP (Model Context Protocol): An open standard specifically built for AI models to discover and connect with external data sources securely.
You’ve already watched this happen
If you’ve ever asked Copilot to create a PowerPoint presentation from a Word document, you’ve watched an API at work.
Copilot uses the document as source material and drafts a presentation in PowerPoint. Under the hood, Copilot asks Microsoft’s API layer (called Microsoft Graph) for the document’s contents, then uses PowerPoint’s own interfaces to build the slides. You don’t see the requests and permission checks happening underneath. You only see the slides appear.
That is the point.
Connecting one is usually the easy part
You probably won’t need to build an API or MCP connection yourself. In many AI tools, someone else has already built it.
Your part is usually to choose the tool, sign in, and approve what the AI is allowed to access.
How to set up Claude Connectors (connect Claude to Google Drive, Slack, and more)
In Claude, these connections are called Connectors (you’ll also hear them called integrations).
Click the + menu beside the chat box
Choose Connectors
Select Manage Connectors
Click Connect, then sign in to that service
Review the request permissions and approve the connection
Once connected, Claude may be able to search for information or perform approved actions, depending on what that Connector supports. For example, it might search files in Google Drive, retrieve information from Slack, or create a task in Asana.
How to connect apps to ChatGPT
ChatGPT calls its connections to services such as Gmail, Google Drive, and Outlook Apps. These were previously called Connectors. You now discover and add them through ChatGPT’s Plugin Directory.
This ChatGPT Plugin Directory launched in July 2026. It's not the old 2023 ChatGPT plugins feature, which OpenAI retired in 2024, so ignore any older articles saying plugins are gone.
Open the Plugin Directory from the ChatGPT sidebar (or Settings > Plugins).
Find the plugin containing the App or service you want to connect, such as Gmail.
Open it and click Connect, if that option is available.
Sign in to the service and review the access being requested.
Approve the connection and enable syncing if the App requires it.
Once connected, you can use the App in a conversation by mentioning it with @, or by selecting +, then More, and choosing the App.
Depending on what the App supports, ChatGPT may search connected information, retrieve files or messages, or perform an action that you approve.
Availability can vary based on your ChatGPT plan, region, workplace settings, and permissions.
Connecting is not the same as building
When you click Connect, you aren’t building an API or writing an MCP server.
You are turning on a connection that someone else already built.
The technical work happened before you arrived. The companies involved decided what information could be requested, what actions could be taken, and how permission would be handled.
Behind those few clicks is the API or MCP plumbing that lets the two programs work together.
This post won’t teach you to build that plumbing. It will help you understand what you’re turning on, what access you’re granting, and what’s happening when one tool reaches into another and gets useful work done.
Connecting an existing tool may take only a few clicks. Building the connection behind that button is the technical part.
Why should a non-coder know this?
Fair question. You’re probably never going to build an API.
The reason this is important is that API is becoming one of the load-bearing words of the work world, just like the cloud became a common word years ago.
Understanding APIs as a non-developer provides several direct professional advantages:
Better software evaluation: You can ask vendors exactly what data their API can read or modify before purchasing new workplace tools.
Improved troubleshooting: You will recognize that when two connected tools stop syncing, the API connection or API key might simply need to be refreshed.
Clearer communication: You can collaborate more effectively with IT and engineering teams by using accurate terminology during software integrations.
Understanding the word helps you follow what’s actually being proposed.
Now you know that one program will be requesting information or actions from another. You also know that the connection has limits. It can only access what the API was designed and authorized to provide.
That gives you better questions to ask:
What can the integration access?
Can it only read information, or can it make changes?
Who built the connection?
What permissions will we be granting?
What happens if the connection stops working?
You don’t need to understand the code underneath it. You only need to understand what the connection makes possible.
Common API questions
Q: What is an API in simple terms?
A: An API is a defined way for one software program to request information or actions from another.
One program sends a request in a format the other understands, and the other program sends back a response. That’s what allows connected tools to exchange information without someone copying and pasting it manually.
Q: What does API stand for?
A: API stands for application programming interface.
The full name matters less than the basic idea: an API gives one program a defined way to ask another program for something.
Q: What's the difference between an API and an API key?
A: An API defines what one program can request from another and how the request must be made.
An API key is one type of credential used to identify the app, account, or project making the request. It helps the service decide whether the request should be accepted.
The API provides the rules. The API key helps prove that the requester has permission to use them.
Q: Do I need to know how to code to use an API?
A: No.
You already use tools built on APIs whenever an add-in searches a photo library, a chart retrieves fresh numbers, or an AI tool accesses an outside service.
Connecting an existing tool may be as simple as clicking Connect, signing in, and approving access. Building the connection itself usually requires technical work, but using it often doesn’t.
Q: Is an API the same as an MCP?
A: No. They are related, but they do different jobs.
An API defines how software can request specific information or actions from another service.
MCP, or Model Context Protocol, is an open standard that helps AI applications connect to outside tools and data in a consistent way. An MCP connection may use traditional APIs under the hood.
MCP doesn’t replace APIs. It gives AI applications a standard way to find and use the capabilities those APIs and other systems provide.
Q: What are Connectors in Claude?
A: Connectors are Claude’s name for the ready-made connections that let Claude work with your other tools, like Google Drive or Slack. You click Connect, sign in, and approve what Claude is allowed to access. Underneath, a Connector runs on the same plumbing this post covers: APIs, and sometimes MCP.
The takeaway: now you speak API
If you remember one thing from this page, make it this:
An API is a defined way for one software program to request information or actions from another.
You were already using APIs all day.
The stock-photo add-in searching an image library. The chart pulling in fresh numbers. The presentation outline moving from your browser into PowerPoint. None of those handoffs is magic. They’re software connections working quietly underneath.
The difference is that now you’ve got a name for them.
The next time someone says, “We’ll connect through their API,” you can follow the conversation, ask what the connection actually allows, and judge whether a vendor’s promise makes sense.
That’s a useful workplace skill wearing a nerdy name. It may also save you from twenty minutes of pretending to understand the meeting, which gets everyone to happy hour sooner.
For more plain-English guides to PowerPoint, AI, and the tools see our other tutorials.
About the Author
Taylor Croonquist
Co-Founder, Nuts & Bolts Speed Training
Taylor Croonquist is a PowerPoint expert and trainer. Over a career spanning the globe, from consulting in New York and investment banking in China, Taylor has truly seen it all in PowerPoint. Through necessity and a natural tech savvy, Taylor honed his PowerPoint skills to the point of even blowing the minds of the Microsoft PowerPoint programming team. When he's not busy crafting PowerPoint training, you can find him reading a sci-fi series or scuba diving.