User
An user can register expenses, mileages and allowances (per diems) but can't do any settings for the organization that that effect anyone else. The user has no access to submitted reports on the organization. 

Administrator 
An administrator can register expenses, mileages and allowances (per diems) for themselves. In addition they can also make changes in settings that effects the whole organization, ie. change approvers, add dimensions or change integrations and see all submitted reports.