XMPP is a protocol for IM (instant messaging), you can find more about it at: http://xmpp.org/
When you are learning the XMPP specifications, you may like (1) to view the XMPP stanzas which are sent and received; (2) to send some customized stanzas to check what will happen under specific condition.
Fortunately, you can get such a XMPP client for free and without writing code, that’s the Spark client which is an open source project and can run on Linux, Mac OS and Windows. here is its link: http://www.igniterealtime.org/projects/spark/index.jsp . Read the rest of this entry »