a text file that looks like a regular HTML web page with embedded JSP code

Java Server Page (JSP) are small java servlet programs that are specified in the Web page and run on the Web server.

An extension to the servlet functionality that enables a simple programmatic interface to Web pages. JSPs are HTML pages with special tags and embedded Java code that is executed on the Web or application server providing dynamic functionality to HTML pages. JSPs are actually compiled into servlets when first requested and run in the server's JVM.

A specification that uses Java Servlets run on the webserver to generate Web pages that feature dynamic content. JSP is freely available, and a competitor...

Java server pages are a way to create dynamic Web content. They may also be used to generate and consume XML between n-tier servers or between servers and clients.