Note: You are currently viewing documentation for Moodle 2.2. Up-to-date documentation for the latest stable version is available here: Capabilities/moodle/site:accessallgroups.
moodle/site:accessallgroups allows a user to access all groups in the given context, regardless of the group mode. For example, a user with this capability set can browse forum posting of other groups when group mode of the forum activity is set to SEPARATE_GROUPS.
In Moodle 1.6 terms, non-editing teachers do not have this capability (bound to own group settings), but editing teachers do.