I've just been wondering what are the differences between the two and I can't seem to find a formal delineation.
Enzyme cofactors are a collective name of all the chemical compunds or elements associated with the enzyme to increase its efficiency. There are mainly two types- inorganic ions and organic compounds. Inorganic ions are also known as enzyme activators (Cl ion in salivary amylase). Organic compunds are again divided into two- co-enzymes and prosthetic groups. Co-enzymes are loosely associated with the enzyme. They can be removed from the enzyme and undergo cyclic reactions to again combine with enzyme (EX: NAD, NADP). But prosthetic groups are tightly associated with enzyme molecules(EX : FAD). Hope this helps.