JSP is a standard developed by enterprise IT giant Sun Microsystems, and is an alternative for Microsoft’s Active Server Pages (ASP). JSP, of course, is an acronym for “Java Server Pages”. There is a similarity between JSP and ASP – both are compiled on the server, not on the client side. In other words, a server compiles JSP and ASP code into HTML readable by a web browser like Firefox or Chrome.
The key difference is that JSP is based, of course, on Sun’s popular Java language. In contrast, ASP makes use of Microsoft’s Visual Basic. Both ASP and JSP can be used to build a dynamic, interactive website including the ability to retrieve data stored in a database while a webpage is accessed.
JSP includes Java mixed throughout the HTML code, but once a JSP page is compiled it is pure HTML – all the Java code is parsed on the server. Note the difference with JavaScript: where JavaScript is used the code is in fact processed by the web browser, as long as the web browser is capable of processing JavaScript.