JAX-WS, which stands for Java API for XML Web Services, is a Java technology for building and consuming web services, specifically SOAP (Simple Object Access Protocol) based web services. It is part of the Java EE (Enterprise Edition) platform but can also be used in Java SE (Standard Edition) applications. JAX-WS simplifies the creation and consumption of web services by providing a set of standard APIs and annotations.

Here are some key points about JAX-WS:

1. SOAP-Based Web Services: JAX-WS is primarily used for building and interacting with SOAP-based web services. SOAP is a protocol for exchanging structured information in the implementation of web services.

2. Annotations: JAX-WS uses annotations to simplify the development of web services. Annotations like @WebService, @WebMethod, and @WebParam are used to define web service endpoints and their operations.

3. Client and Server: JAX-WS provides both client and server APIs. Developers can create web service clients to consume remote web services, as well as create web service endpoints (servers) to expose their own services.

4. Java-to-WSDL Mapping: JAX-WS includes a tool called wsimport that generates Java classes from a Web Services Description Language (WSDL) document. This makes it easier to create client code for a web service by generating the necessary Java classes from the service’s WSDL.

5. Endpoint Implementation: To create a web service endpoint, you typically implement a Java class and annotate it with @WebService. This class defines the operations that the web service provides.

6. Client Proxy: When creating a web service client, you can generate a client proxy using the wsimport tool or IDE integration. This proxy allows you to invoke web service operations in a manner that feels like calling local Java methods.

7. Integration with Java EE: In Java EE applications, JAX-WS can be easily integrated with other Java EE technologies like EJBs (Enterprise JavaBeans) and JPA (Java Persistence API) to build enterprise-level web services.

8. Transport and Message Handlers: JAX-WS allows you to define handlers that can intercept and process messages at the transport and message level. This is useful for tasks like authentication, logging, and message transformation.

9. Security: JAX-WS provides support for securing web services using various security mechanisms such as WS-Security and SSL/TLS.

10. Interoperability: JAX-WS aims for interoperability with other web service stacks and platforms. It follows web services standards to ensure compatibility with services developed in different technologies.