What is RIA?

I recently encountered this word RIA in context of web-applications and do not had the clue what it was so here it is:

"Rich Internet applications (RIA) are web applications that have the features and functionality of traditional desktop applications. RIAs typically transfer the processing necessary for the user interface to the web client but keep the bulk of the data (i.e., maintaining the state of the program, the data, etc.) back on the application server."

RIAs typically:

• run in a web browser, or do not require software installation
• run locally in a secure environment called a sandbox

More information available on enclyclopedia : http://en.wikipedia.org/wiki/Rich_Internet_application