In Java Servlets, attributes are used to store information that is shared between different parts of a web application. Attributes can be set, retrieved and removed using the ServletContext, ServletRequest, and HttpSession interfaces.

The ServletContext interface provides a way to store and retrieve application-wide attributes. These attributes are available to all servlets and JSPs within the application. The setAttribute() method is used to store an attribute, while the getAttribute() and removeAttribute() methods are used to retrieve and remove an attribute, respectively.

The ServletRequest interface provides a way to store and retrieve request-specific attributes. These attributes are only available to the servlet that handles the request. The setAttribute() method is used to store an attribute, while the getAttribute() and removeAttribute() methods are used to retrieve and remove an attribute, respectively.

The HttpSession interface provides a way to store and retrieve session-specific attributes. These attributes are available to all servlets and JSPs within the session. The setAttribute() method is used to store an attribute, while the getAttribute() and removeAttribute() methods are used to retrieve and remove an attribute, respectively.

Attributes can be of any Java object type, including primitive types, arrays, and user-defined types. Attributes are useful for sharing information between different parts of a web application, such as user preferences, database connections, and application configuration settings.