Servlet vs JSWDK

[Xu Jianwu]

java.sun.com/products provides a stand-alone Servlet API download and a JSWDK download which includes JSP API, JSP engine, Servlet engine and Servlet API. But the Servlet API in JSWDK is different from the stand-alone one. So what is the difference? Can I use the stand-alone one without install JSWDK (my web server is Apache on linux 6.1)?