What is the difference between <%@ include file="abc.jsp" %> and <jsp:include page="abc.jsp" %> ?
The <%@include file="abc.jsp"%> directive acts like C "#include", pulling in the text of the included file and compiling it as if it were part of the including file. The included file can be any type (including HTML or text).
The <jsp:include page="abc.jsp"> tag compiles the file as a separate JSP file, and embeds a call to it in the compiled JSP.
See also this question in the JSP FAQ.