Every organization is a tenant, regardlessof whether it is a customer organization or a partner organization. The terms 'organization', 'org' and 'tenant' is the same thing and are used interchangeably.
In every API call the orgId is fix part of the URL. In the following example all TicketDefinitions of organization 1234 are requested: https://api.campos.ch/1234/v1/Tickets/TicketDefinitions
There are two scenarios:
a single organization operating on itself (main scenario)
a partner organization operating on multiple organizations (their customers)