What is a herald?

Heralds today have no particular role outside of ceremonial duties. However, in Medieval times they were very important. They served as diplomats, carrying messages to other countries, particularly to enemy armies in times of war, as town criers, announcing proclamations and messages throughout the towns, villages and cities, as observers in a battle, deciding who won if it was unclear, and also as a handy Heraldic Encyclopedia, identifying both living knights (whether enemy for targeting or friendly for identification) and the dead knights to get their identities by their heraldry (the insignia on their surcoats). This was a very handy skill because everyone looks the same in armour, and so their coats of arms were the only way of identifying people.