Cryonics: The Issues - An introduction by Canadian Ben Best, 8 printed pages. www.benbest.com/cryonics/cryiss.html
Nanotechnology and Cryonics - An introduction by Jerry Emanuelson of Colorado Futurescience. 3 printed pages. www.webcom.com/cfsc/nanocryo.html
Ralph Merkle's Cryonics Introduction - Short and useful, but not really "simple." It assumes some knowledge of cryonics already, so read some others first. 3 printed pages, with several internal hyperlinks to other explanations or web pages. merkle.com/merkleDir/cryo.html
The Cryonics Thesis - The why of cryonics, as understood by the Cryonics Institute. www.cryonics.org/reprise.html