The system has numerous edit screens which all work the same way as the following example (the Customer Information edit screen).

The screen consists of three areas:
(1) basic information - this area contains the things that there is only one of for the item being edited

(2) the bottom buttons as follows: (there may be others as well but these are the standard ones)
Apply - update the item with the changes made but do not close the screen
OK - apply the changes made and close the screen
Cancel - close the screen losing any changes made. Note that if you have previously used Apply, then the 'applied' changes will not be lost.

(3) the tab area - this area contains the tabs for the sub-items of which there are usually more than one - in the above example there are 7. The tab area consists of three or more sub-areas as follows:

(4) the tab buttons as follows:
Add - add a sub-item - you will be able to enter it's details, and if you then click Add a second time, those will be accepted and cleared to allow you to enter another sub-item. Note that the tab button line will sometimes contain pull-downs that allow you to select the type of sub-item being added - in the above example you can see that there is a pull-down to select the type of contact.  If so, you will need to select the type before clicking the Add button.
Delete - delete the current sub-item
Previous and Next - these are used to navigate backwards and forwards though the sub-items changing the currently selected one. The buttons will be disabled (greyed out) when you are at the beginning/end of the sub-items.

(5) sub-item table - this displays the sub-items - click on one to select it

(6) sub-item details - here you can enter/view the details of the current sub-item

(7) sub-item tabs - if needed there will be tabs here to allow the editing of part of the sub-item. In the above example you can see there is a Purpose tab to allow the purpose of the contact to be set.