Prezi is an interactive website that enables you to create presentation aids. However, it is unlike other presentation aids in the sense that it is organized as a concept map.
Prezi's basic service is completely free. To get started, simply create an account at prezi.com
Additionally, to use Prezi's basic service, you do not need to download any software. You can use the web-based platform.
Open and/or print the PDF Prezi Basics tutorial form more information.