Webhook vs Callback: What's the difference?
Webhooks and callbacks are both useful ways of executing event driven functions. However, they are separate concepts and applied in many different scenarios.
Let's start by defining them.
Webhooks are a method of communication between two applications or services, where one service sends an HTTP request to another when a specific event occurs. The receiving service, also known as the subscriber, sets up a URL endpoint that listens for incoming webhook requests. Webhooks are often used in event-driven architectures and are an efficient way to keep systems in sync, as they enable real-time updates and notifications.
Callbacks, on the other hand, are functions that are passed as arguments to another function and are executed at a later time or upon the completion of a specific task. In the context of programming, callbacks are often used for asynchronous operations, such as handling the response from an API request or processing user input in a graphical user interface.
Both webhooks and callbacks serve as mechanisms for handling events and can help create more responsive and dynamic applications. They both involve one component or service sending information to another, typically as a reaction to some event or state change.
However there are some major differences:
- Communication method: Webhooks use HTTP requests for communication between services, whereas callbacks involve passing a function as an argument within the same application or programming environment.
- Scope: Webhooks are generally used for communication between separate applications or services, often across different domains or environments. Callbacks, on the other hand, are used within a single application or environment, usually for managing asynchronous operations or handling user interactions.
- Language and platform: Webhooks are language-agnostic and can be used for communication between services written in different programming languages or running on different platforms. Callbacks are typically language-specific, as they involve passing a function within the same programming environment.
- Synchronous vs. asynchronous: Webhooks are inherently asynchronous, as they are triggered by an event and do not expect an immediate response. Callbacks can be used for both synchronous and asynchronous operations, depending on the specific use case and implementation.
In summary, webhooks and callbacks are both mechanisms for handling events and enabling communication between components, but they differ in terms of scope, communication method, language, and platform compatibility. Webhooks are used for communication between separate services, while callbacks are typically employed within a single application or programming environment.