JSP standard actionAn action that is defined in the JSP specification and is always available to a JSP page.
JSP tag fileA source file containing a reusable fragment of JSP code that is translated into a tag handler when a JSP page is translated into a servlet.
JSP tag handlerA Java programming language object that implements the behavior of a custom tag.
JSP tag libraryA collection of custom tags described via a tag library descriptor and Java classes.
JSR (Java Specification Request)Java Specification Request (JSR) is the actual description of proposed and final specifications for the Java platform.