Explain the features are in Servlet 3?

Servlet 3.0 is an update of Servlet 2.5. Servlet 3.0 focuses on extensibility and pluggability. Key features in Servlet 3.0 can be categorized into the following areas:

• Easier development with annotations.
• Web application modularity.
• Asynchronous Servlet.
• Programmatic instantiation of Servlets/Filters.
• Security Enhancements.