The original Cybermen were unique, their design and build stands out from the other Cybermen as they were still evolving. These are the only Cybermen from the TV series to still have human elements, the hands are still human and the face is still partly flesh. The rest of the body on the outside appears cybernetic.
The Mondasian Cybermen drew their power from Mondas. When Mondas was destroyed so were they. The Cybermen knew their home planet was losing power and weakening, this is why they returned to Earth.
These Cybermen only appeared in the 1966 story The Tenth Planet.
KrailCome to Mondas and you will have no need of emotions – You will become like us