The numbers of allowed bookings on an event can be restricted in two ways:
1) The total number of attendees allowed at an event can be set using the 'Entry setting - Maximum attendees' option. This sets the number of spaces or places or capacity in terms of numbers of people allowed at the event. It can be left blank for unrestricted numbers.
2) The other option is to restrict ticket numbers. Each ticket on the event has a 'Number available' option. With multiple tickets each with a limit set, this adds up to set the total spaces. Also, a ticket can be a 'group ticket' in which case the capacity is the maximum group size times the number of tickets.
Ticket availability and maximum attendees are combined to calculate the total possible attendance, with total attendees taking precedence over ticket numbers.
Once an event is full, the waiting list is activated and prospective attendees will be able to add themselves to the list.
The numbers shown on the right of the schedule list let you quickly see the number of attendees (+ people waiting) / the total spaces. The number of attendees includes people on bookings reserved in the checkout.