to update your working copy to a log item’s revision.The log displays the log items for the selected file or folder in a verbose, top-down style which is similar to the output of the svn log command.
Log items are displayed in descending order with the newest item show at the top of the view.
If issue tracking support is enabled (see Integrating with Issue Tracking Systems for more information), matching issue numbers in log messages are displayed as links. Clicking on the link will open a browser window on the issue’s page in the issue tracking system.
For working copy items, the working revision is marked with a working badge.
Click the update button to update your working copy to a log item’s revision.
Click the revert button 
to revert your working copy to a log item’s revision.
If your working copy contains uncommitted changes then Cornerstone will ask how to proceed, giving you the option of either keeping or discarding the changes.
Click the share button 
to share a log item.
You can choose which items appear in the Share menu by using the Extensions pane of System Preferences.
Each log item contains a list of the files which were changed in that revision. The changed files are grouped by action (i.e. additions, deletions, modifications and replacements).
A change can be selected by single-clicking the change’s filename. Double-clicking a change’s filename shows the changes made in that revision in the compare view.
A log item’s change set is collapsed by default. It can be expanded by clicking on the Changes section title.