Workspace > Events > Event PagesEvent Setup step, Levels tab, the following fields can be set for the ticket level:

Qty. Avail. - limits the overall quantity of tickets available for the Level for the event.

Level Purch. Limit - limits the number (quantity) of tickets allowed to be purchased at one time for the Level.

# of Attendees Per Purchase - issues one or more tickets (attendees) per quantity selected and, optionally, captures attendee info and custom attendee fields.

An example when this would be set to greater than one is a sponsor ticket that allows X attendees to the event.
Also, this field can be set to 0 (Zero Attendee Event Levels) which indicates no tickets are issued or attendees captured; the ticket Level purchases are not included in Workspace > Events > Event Attendance.