There is not a certification called ADM231, rather there is a course called Intro to Object Oriented Programming for Admins, whose course code is ADM231.

Certifications are:

- Certified Administrator

- Certified Advanced Administrator

- Certified Developer

- Certified Advanced Developer

- Certified Sales Cloud Consultant

- Certified Service Cloud Consultant

- Certified Technical Architect

There are some courses that are closely tied to a certification (for example Administration Essentials for New Admins (ADM201) is correlated to the Certified Administrator credential), but no certification should be referred to as ADM201 certified/certification.

Make sense?