Web APIs are like the silent interpreters working behind the scenes of the internet. They talk to everything, know everything—and don’t make a sound. Without them? Online shopping would be chaos, banking apps wouldn’t work, and your smartwatch would be…well, just a watch.
Sounds more important than you thought? It is! This article discusses what web APIs are, how they work, and where they’re used every day.
What Is a Web API?
Web APIs (Web Application Programming Interfaces) are interfaces that allow different software applications and web services to interact over the internet.
They receive requests, process them, and send back structured responses. Web APIs use the HTTP protocol for communication—just like loading a web page in your browser.
How Does a Web API Work?
Web APIs operate on a sender–receiver principle, acting as intermediaries for data exchange between client and server. Here’s how it works:
1. Request by the Client (Sender).
An application (like a browser, mobile app, or javascript front-end) sends an HTTP request to the web API. This request includes:
- A URL as the endpoint
- An HTTP method (GET, POST, PUT, DELETE)
- Additional data (for POST/PUT)
- Authentication info
Common HTTP Methods:
- GET: Retrieves data (read-only)
- POST: Creates new data
- PUT: Updates existing data
- DELETE: Removes data
2. Processing by the Server (Recipient).
The web API receives the request, checks it, authenticates if needed, and performs the requested action—like fetching from a database.
The API sends back an HTTP response with:
- Status codes (e.g., 200 OK, 201 Created, 404 Not Found)
- Data in JSON or XML
- Any error messages
3. Response to the Client.
The API sends back an HTTP response with:
- Status codes (e.g., 200 OK, 201 Created, 404 Not Found)
- Data in JSON or XML
- Any error messages
This standardisation enables smooth communication across various frameworks and web services.
Web API vs REST API?
The question “What’s the difference between a REST API and a web API?” can be reframed as: How are they related?
A web API is a broader concept—it’s any API accessible over the web. A REST API is a specific type of web API built on REST (Representational State Transfer) architecture.
But not all web APIs are RESTful. They might use SOAP, GraphQL, or other protocols. For example, ASP.NET Web API lets developers build REST APIs easily using the .NET framework.
Working with Web APIs in Practice: JSON, XML, and HTTP Protocol
When building modern web applications, developers rely on web APIs to connect a wide range of clients including browsers, mobile apps, and third-party services. Web APIs provide an interface that allows programmers to accessfeatures or data using HTTP requests and standard content formats like JSON and XML.
Many browser APIs are built-in, like the Geolocation API, Web Storage API, DOM manipulation, and Fetch API for ajax calls, letting javascript developers get the data they need without leaving the browser environment. For example, jQuery simplifies ajax requests, while CSS and HTML ensure a smooth user interface.
On the server side, frameworks like ASP.NET Web API, ASP.NET Core, and WCF offer a framework for buildingsecure and scalable REST APIs and web services. These apis need careful api management, versioning, and security, including authentication and dependency injection patterns.
A well-designed web API uses clear syntax and robust routing to map uris to controller actions, returning action results with json data or XML responses. This standardisation supports interoperability across mvc architectures, mobile apps, and web-based front-ends.
APIs also enable api gateways and open-source integrations, letting businesses build web-based ecosystems and marketplaces. By using APIs, companies can automate workflows, streamline communication between client and server, and provide consistent user interaction across platforms.
Whether you’re working with Node.js, Python, or .NET, understanding web API vs other web services is key to choosing the right approach for your web application and delivering a great digital experience.
Types of Web APIs.
Web APIs can be built using different architectures, tailored to data formats, security needs, or real-time requirements. Here’s an introduction:
REST (Representational State Transfer).
REST APIs are popular because they’re simple and flexible. They use standard HTTP methods, making them easy to use for web applications, mobile apps, and browser clients.
REST APIs are stateless—the server doesn’t store info about past requests—and often deliver JSON data, making them lightweight and scalable.
SOAP (Simple Object Access Protocol).
SOAP APIs are more formal and use an XML-based format. They’re protocol-agnostic (can use HTTP, SMTP, etc.) and known for strong security features, making them common in finance and healthcare.
GraphQL.
Developed by Facebook, GraphQL uses a single endpoint. Clients specify exactly what data they need, avoiding over-fetching. Ideal for e-commerce systems and mobile apps with limited bandwidth.
WebSocket.
WebSocket APIs maintain an always-open connection for real-time communication. Perfect for live chats, gaming, or real-time data streaming.
3 Examples of the Use of Web APIs.
Web APIs improve how companies deliver web services and web applications by simplifying data access and integration. Developers often use popular languages like Python or JavaScript to consume web APIs, parse JSON or XML data, and integrate services into their web applications.
E-Commerce.
Web APIs connect online stores to payment providers, shipping services, and review platforms. The interface ensures smooth, automated transactions.
CRM-Systems.
Web APIs integrate CRM platforms with email marketing, social media platforms, and other tools—creating a unified customer experience.
Internet of Things.
In IoT, web APIs let sensors communicate with central systems—for automation in industry, healthcare, and agriculture.
The Lobster Data Platform: Easily Manage and Integrate Web APIs for Modern Applications
Lobster’s central data platform helps you manage and integrate all your web APIs in one place—whether on-premises, in the cloud, or as a hybrid solution.
Secure your APIs with robust authentication and encryption. Build custom dashboards to monitor and analyse your APItraffic and json data.
Use over 90 pre-built connectors to integrate your web APIs effortlessly—no coding required. Our platform lets you focus on your business, not the tech.
