What is a CEU?
A CEU (Continuing Education Unit) is a currency that measures a person's participation in a formal, non-credit continuing education program, such as a workshop, seminar, tutorial, or self-study course. As defined by the ANSI / IACET (American National Standards Institute / International Association for Continuing Education and Training) which are widely recognized as standards of good practice internationally.  

One CEU is equal to ten contact hours of instruction in a continuing education activity.  Any activity less than one hour in duration is not eligible for CEUs.

Currently, thirty states (PDF, 57 KB) require Professional Development Hours (PDHs) to maintain P.E. licensure, encouraging engineers to seek CEUs for their participation in Continuing Education Programs. IEEE CEUs readily translate into PDHs. 1 CEU = 10 PDHs. Earning CEUs helps engineers meet company training requirements.

Learn more about IEEE CEUs.

The IEEE is an Authorized Provider of CEUs. 
IACET CEU Provider #1255

IEEE and CEUs
IEEE maintains an official registry of all CEUs awarded. This makes accounting to state licensing boards an easier task for engineers.  It also helps IEEE  keep track of seminar / tutorial participants.