Views are useful for the staff members as it helps them to decide what they want to see in the quick glance in the ticket listing. Depending upon these fields it would appear in the ticket listing. There can be different views that can be set for the logged in staff member accordingly.
Login to the staff portal or manage portal.
Click on the name of the logged in staff and it will display the drop down for it.
Go to the Profile Tab >> Views >> Add.
The desired title is to be given for the views and from the List column the particular fields are to be selected from the fields that are available.
The particular view can be added from the Add option.
Depending upon the views that are added, the fields would appear in the ticket listing.