In vibration at creation of web applications on a daily basis, we deal with the connection of external systems, and therefore today we will look at various options for connection via API.
API (Application Programming Interface) is an acronym that appears more and more in the technological world. But what exactly does API mean? Basically, it is a set of rules and protocols that allow different software systems to communicate and exchange data. An API provides programmers and developers with a set of functions and interfaces through which they can access certain services, data or functionality of another application or platform. In this way, the API simplifies the integration of different systems, enables the development of new applications and creates space for expansion and cooperation between different technological solutions.
The article was revised and updated in May 2026. Check with specific service providers for technical information.
Pri application development choosing the right API architecture is a key factor. There are several different types of API architectures that are used for different purposes and in different contexts. In this article, we'll go over some of the most commonly used types of API architectures: SOAP, REST, GraphQL, gRPC, WebSocket, and Webhook. We will compare their characteristics and properties.
SOAP (Simple Object Access Protocol)
SOAP is a protocol for exchanging structured messages between systems. In this type of architecture, the emphasis is on data accuracy and formatting. SOAP uses XML to represent data structures and WSDL (Web Services Description Language) to describe APIs. It is based on the range of operations (RPC - Remote Procedure Call) and communication takes place through protocols such as HTTP, SMTP and others. SOAP is robust and supports encryption and digital signatures, but its implementation can be more complex and performance is often slower compared to other architectures.
REST (Representational State Transfer)
REST is an architectural style for the design of distributed systems, where the emphasis is on simplicity, scalability and efficiency. REST uses the HTTP protocol and its methods (GET, POST, PUT, DELETE) to manipulate resources using individual URIs (Uniform Resource Identifiers). REST uses representations of resources (resources) in a format such as JSON or XML. It is a popular choice for web APIs because it is easy to implement and compatible with most clients and servers.
GraphQL
GraphQL is an open query language and API architecture style developed by Facebook. Unlike traditional APIs, where a pre-defined set of data is retrieved based on fixed endpoints, GraphQL allows clients to specify exactly what data they need. In this way, the transfer of unnecessary data is minimized and the number of requests to the server is reduced. GraphQL uses its own type system to describe data, and clients may require specific fields, relationships, and transformations. GraphQL is flexible but requires more effort to implement on the server side.
gRPC
gRPC is a modern and powerful framework for creating APIs developed by Google. It is based on the HTTP/2 protocol and uses the binary message format Protocol Buffers for fast and efficient communication between clients and servers. gRPC supports various programming languages and allows you to define services and their methods using an interface defined in a .proto file. It is known for its high speed, efficiency and automatic code generation for clients and servers.
WebSocket
WebSocket is a protocol that allows two-way communication between a client and a server in real time. Unlike traditional HTTP, which is based on the principle of one-way requests and responses, WebSocket maintains a persistent connection that enables fast and efficient communication. It is suitable for applications where immediate notification of changes is required, such as chat applications or rapid content updates.
Webhook
A webhook is a mechanism that allows applications to catch and respond to events that occur in another application. Instead of clients periodically polling the server for new data, the server sends asynchronous notifications (HTTP POST) to a specified client endpoint (URL) when a certain event occurs. Webhooks are often used to integrate and automate processes between different systems.
In the "API Speed" column, I rated the speed of each API architecture on a scale of 1 to 10, with 10 being the fastest. Speed values are only approximations and may vary depending on the specific implementation and infrastructure. These values serve as indicative indicators for comparing the speed between individual types of API architectures.
For your interest, see also the timeline when each type of architecture was released
Conclusion
Each API architecture has its own advantages and uses. Deciding which architecture to use should be based on your project's requirements and goals. SOAP is robust and precise, REST is simple and scalable, GraphQL is flexible, gRPC is powerful, WebSocket enables real-time communication and Webhooks provide asynchronous notifications. Comparing and understanding these types of architectures will help you correctly choose the most suitable architecture for your needs.
