This may sound weird but what determines whether a string is packaged blue/red or yellow or does it have no meaning whatsoever? ^^
1) Good answer. 2) Because it is called copper top. 3) may be yo next want to change the package design to reflect the characteristic of the string? for example, yellow/black is for durability and red/black is for sound and blue/black is for high repulsion? I really don't know either...
Lol! Plagerism from the motto!. Aside from that which would explain it, just the question without the motto it would not of explained it. I should of said Energizer!
It's a marketing scheme and it also categories which string fits best into which colour. Durability, Repulsion or Hitting Sound.