power user

A power user, also called a super user, is someone whose computer skills are better than those of an organization's average end user. 

The skills and expertise that an organization's power users possess can be a double-edged sword.  On the one hand, a tech-savvy employee might make a great turnkey trainer or quality assurance tester (QA tester). On the other hand, assigning power users the access rights that are necessary to carry out those tasks can lead to inconsistencies that cause configuration drift and jeopardize security.  

SAP, Oracle and Microsoft have created leadership training programs to turn regular users into power users.