Concerning the Revised Edition
Today's Mizar is beginning to be used increasingly in a large field of applications and it came to have a WWW homepage on the Internet. With support from the users and for the sake of its processing ability, Mizar has managed to renew its version frequently. We hope to help people who are learning Mizar by summarizing those improvements as well as we can.
Concerning the 4th Edition
The content of this note is based upon Mizar version 6.1.12.