Struts2 is an open source framework which is used to develop the web application for Java by using MVC2 architecture.
Struts1 was introduced in 2004 then Apache joined with Open Symphony and created Struts2.
Struts1 + Web Work2 = Struts2
Open Symphony developed the framework which is known as Web Work2.
Types of framework
1. Invasive: It has some rules and regulations which need to be followed anyhow. For example if a path is defined then we have to place the file on that particular path only. Struts, JDBC are the examples of this type.
2. Non-Invasive: It doesn't have certain rules and regulations. Hibernate, Spring are the examples of this type.