How to change an employees department or edit the department names:

First off, if you want to prevent your employees from changing their own departments or titles, head to 'Setup' > 'Preferences' and scroll down to the 'User Profiles' section. From here you can select 'Allow users to change their own department.'

A great place to go check on your current Department titles is the 'User Management' report. This is found by heading to 'Insights' > 'Community and Teams' > 'User Management'.

In this same report you can use the pencil icon to change individuals employee info, including departments. When you click on the pencil icon you will be met by the screenshot below showing the employee's info. Simply change the current department and click 'Save'!

You also have the option to edit or change departments in the Team Import. Go to 'Setup' -> 'Team' -> 'Bulk User Upload' and click 'Download Current Template'. This will download an excel file with each current user's information. You can change Department names in this file and then save it and upload it as a full upload. This will update any changes, including Department names, to users profiles. This is typically a better way if you need to make many changes.