Pulsate Segment is a tool of grouping users matching a specified criteria list. It consists of one or more groups, which in turn consist of one or more rules.
To be matched by a segment group, user has to fulfill any of the criteria specified by its rules. However, to belong to a segment, user has to be matched by all of its groups.
Let's say one wants to create a segment that matches all users named "Phil" or "Mark", who entered a specified geofence twice. It would have two groups, one containing two rules: "first name is Phil" and "first name is Mark", second one containing just one rule: "been at geofence two times".