Understanding APIs and Their Role in Modern Products
A 7-part API series for non-engineers — Part 1
APIs are central to how modern digital products operate, yet they are often discussed in ways that assume technical background or prior experience. This article begins a 7-part series titled “APIs for Non-Engineers,” designed to offer clear, accessible explanations of how APIs work and why they matter.
If you encounter any unfamiliar terms, you can refer to the glossary provided here.
This first part introduces what APIs are and explains how they support the structure and functionality of contemporary applications.
What an API Is — In Practical Terms
An API, or Application Programming Interface, is simply a structured way for one system to communicate with another. When an application needs information or needs to trigger an action elsewhere, it uses an API to make that request.
A useful analogy is the interaction between a customer and a waiter in a restaurant:
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The customer expresses a clear request.
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The waiter carries the request to the kitchen.
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The kitchen prepares the response.
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The waiter returns with the result.
The waiter is not responsible for cooking the meal, and the customer does not need to understand how the kitchen operates internally. The API serves this same intermediary role in software systems. It carries requests, returns responses, and allows each system to remain focused on its specific responsibilities.
This separation is not merely convenient, but is essential. Modern software is built from many parts that must work together reliably without exposing unnecessary internal details.
How APIs Shape the Products We Use
Most products today rely on both internal APIs (used within the same company or system) and external APIs (provided by third parties such as payment, messaging, or identity services). Although these connections are largely invisible to users, they determine the features a product can offer and how those features behave.
Common examples include:
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Logging in using an external identity provider
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Processing payments
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Retrieving customer data
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Sending notifications
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Displaying maps or location information
From a product standpoint, APIs allow teams to put together features by using existing services instead of building everything themselves. For example, a product can use a payment provider’s API rather than creating its own payment system from the ground up. In the same way, it can rely on a messaging API to send notifications or a mapping API to display locations.
By combining internal functionality with these established external APIs, products can deliver more features in less time. They also benefit from the stability, security, and ongoing improvements provided by the external service, which reduces the amount of maintenance required internally.
Why APIs Matter for Non-Technical Roles
Even if you are not responsible for writing API calls, understanding their purpose and behavior improves communication across teams. Many planning conversations, customer interactions, and troubleshooting discussions depend on concepts such as requests, responses, permissions, and system boundaries.
A high-level understanding of APIs helps you:
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set accurate expectations for delivery timelines
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understand why certain features are feasible or limited
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interpret system behaviors that might otherwise appear unpredictable
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communicate more effectively with engineering and design teams
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support customers with clearer explanations
This series aims to provide that understanding without requiring any technical background.
Where APIs Fit Within a Product Architecture
Although product architectures vary, APIs typically operate at the point where one system needs to obtain information or trigger an action in another. A simplified flow looks like this:
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An application identifies a need (e.g., “retrieve user details”).
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A request is prepared, following a specific format the receiving system understands.
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The API transmits the request to the appropriate internal or external service.
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The application uses the returned data to update the user interface or continue its internal workflow.
This process occurs continuously in nearly every digital interaction, often multiple times per second.
Understanding this structure helps clarify why certain operations take time, why errors occur, and why some features depend on third-party availability.
Preparing for the Next Article
This introduction establishes a shared foundation for the rest of the series.
If any definitions in this article felt unfamiliar, the glossary here provides concise explanations you can return to throughout the series.
The next article will explore the “Anatomy of an API Request”, how requests and responses are structured, what information they carry, and how systems interpret them. This understanding will serve as the basis for interpreting real-world API behavior later in the series.
Test Your Knowledge
Take a quiz to test your knowledge of APIs, their role in modern products, and how they enable systems to communicate by clicking this button: