CE Marking is the symbol as shown on the top of this page. The letters "CE" are the abbreviation of French phrase "ConformityEuropean" which literally means "European Conformity". The term initially used was "EC Mark" and it was officially replaced by "CE Marking" in the Directive 93/68/EEC in 1993. "CE Marking" is now used in all EU official documents.
Product Directives contains the "essential requirements" and/or "performance levels" and "Harmonized Standards" to which the products must conform. Harmonized Standards are the technical specifications (European Standards or Harmonization Documents) which are established by several European standards agencies (CEN, CENELEC, etc).
CEN stands for European Committee for Standardization.
CENELEC stands for European Committee for Electro technical Standardization.