Jersey and Jetty are both popular frameworks used in web development. While they are often used together, they have distinct differences that set them apart. Here are the key differences between Jersey and Jetty:

1. Container vs. Framework: Jersey is a lightweight framework that provides an API for building RESTful web services. It focuses on implementing the JAX-RS specification and does not include its own HTTP server. On the other hand, Jetty is a full-fledged HTTP server and servlet container that can run web applications built with various frameworks, including Jersey.

2. Purpose: Jersey is specifically designed for creating RESTful web services. It provides advanced features for handling HTTP requests and responses, such as support for resource mapping, content negotiation, and response caching. Jetty, on the other hand, is a general-purpose web server and servlet container that can handle a wide range of web applications, including RESTful services.

3. Ease of Use: Jersey is known for its simplicity and ease of use, making it a popular choice for developers getting started with building RESTful services. It provides a high-level API that abstracts away many low-level details and allows developers to focus on the core functionality of their services. Jetty, while more powerful and flexible, can be more complex to set up and configure due to its broader scope and support for various web application architectures.

4. Scalability and Performance: Jersey is designed to be lightweight and efficient, making it suitable for small to medium-sized applications. It efficiently handles a large number of concurrent requests and provides mechanisms for scaling up the application as needed. Jetty, on the other hand, is known for its scalability and performance, making it a preferred choice for large-scale web applications that require high throughput and low latency.

5. Ecosystem and Community: Jersey has a strong community and ecosystem built around it, with a rich set of plugins, extensions, and documentation available. It is backed by the larger Java community and has a dedicated development team. Jetty, being a more general-purpose web server, also has a thriving community and ecosystem but with a broader focus on servlet-based web applications.

6. Deployment Options: Jersey can be deployed on any servlet container like Jetty, Tomcat, or even within an application server like GlassFish or WildFly. However, Jetty provides a standalone server that can be easily embedded within an application, allowing for more flexibility in deployment options.

In Summary, Jersey is a lightweight framework for building RESTful web services, while Jetty is a versatile web server and servlet container. Jersey focuses on simplicity and ease of use, while Jetty offers more flexibility and scalability options. Both have their strengths and are widely used in the web development community.