Post: #3

I'll try a quick answer. Correct me if I'm wrong.
If the tag/var/whatever contains only numbers its stored as a number.
If it contains some chars - comma, question mark, anything from alphabet, etc. It's stored in some shitty coding. Unicode, UTF8,16,32. In this case it should be common ASCII. So, 2 bytes(7 or 8bits) per char.

Logically, more letters means more memory. Even tags itself "shouldn't be" named like tag.the_most_awesome_person_in_the_world="me" but tag.bestperson="me".

Shorter = better but it must be understandable.