From a modern point of view heraldry is art, history, and in an elemental form the ancient descendant of flags, logos, and trademarks.
Today you can not use certain icons or logos without permission from the owner, likewise in the middle ages heraldic designs were 'owned' by affluent and high society. Using it without permission was illegal and could have resulted in legal action. Thus today, if you use certain corporate logos without permission like the Nike swoosh, they can come after you with a pack of hungry lawyers.
There is no accident that heraldry sounds a bit like hereditary - since the early versions of a coat of arms was inherited.
Essentially an image can be owned and use of those images without proper procedure may cause result in grief, especially if money is involved.
The foundation of heraldry rests solidly on the symbols of a warrior's shield.
The designs, patterns, and icons found on a warrior's shield have always been important. All the civilizations of the world from the aboriginals of America, tribal Africa, the feudal houses of Japan and Europe have held this art-form in high esteem.
It was in Europe near the end of the first millennium when Heraldry received its codified reputation through the elite families of Europe.
However battle shield art was not invented in Europe, since this holy rite was practice by all the literate by book and literate by nature tribes of the world.