There are millions of possible objects that can be described in science, too many to create
common names for every one. As a response, a number of systems of systematic names have been created.These can be as simple as assigning a
prefix and a number to each object (in which case they are a type of
numbering scheme), or as complex as encoding the complete structure of the object in the name. Many systems combine some information about the named object with an extra sequence number to make it into a
unique identifier.
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