You may programm a myriad of different channels for you radio. To organize them in handy chunks zones are used. That is, a zone is just a named list of channels that are relevant for a particular area.
The Zones just lists all defined zones. You may add a zone using the Add Zone button or you may delete one by selecting the zone in the list and clicking on Delete Zone. You may also alter the ordering of the zones by selecting one from the list and using the up and down buttons on the right.
How zones are implemented differs from radio to radio. For example, some radios allow to set a different zone for each VFO (A or B), consequently these zones are simple lists of channels. Other radios allow to select a single zone for both VFO. Usually, for these radios a zone consists of two lists of channels. One for each VFO. qdmr zones follow the second approach. That is, a zone consists of two lists. One of each VFO. When programming radios that support only one list per zone, the zone is split into two. One of each list.
Double-clicking a zone or clicking on the Add Zone button will open the zone editor dialog.
This dialog allows to add, remove and change the order of the channels within the zone.