What is a post-nominal?

Post-nominal letters, initials and titles, are letters placed after the name of a person to indicate that the individual holds a position, educational degree, accreditation, office, military decoration, honour, or is a member of an institute. An individual may use several different sets of post-nominal letters, but in some contexts, it may be customary to limit the number of sets used. The order in which these are listed after a name is based on an established ‘order of precedence’ and categorisation of awards.