The best armour for a Warrior is Plate. You can only wear plate from Level 40 onwards, until then wear Mail.
Warriors can upgrade from mail to plate armor at level 40.
Leather armor on WoW is worn by rogues, shamans, and druids. "Clothies" or characters who can only wear cloth armor are the magic users - warlocks, priests, and mages. Warriors, paladins, and death knights can wear mail and plate armor.
Only certain classes are allowed to wear mail armor. Warriors and paladins start out in mail armor, until level 40 when they train to wear plate. Hunters and Shaman can wear armor starting at level 40 by going to their class trainer and learning the ability.
Mail armor is worn by warriors and paladins from when they first start until level 40 when they get access to plate armor. Shaman and hunters wear leather until 40 when they get access to mail armor. Although Death Knights start at 55 and therefore start in plate armor, they can wear mail armor, although that probably isn't a good idea as DK's are melee and need the armor to survive. No other class is allowed to wear mail armor.
There is no such thing as dragonwarrior armor on runescape. If you mean dragon plate armor, you need to have level 60 defense to be able to wear it. Dragon plate armor has good defense bonuses, but it is a little expensive. To get dragon plate armor you can but it at the grand exchange or buy ir from players. Some monsters on runescape drop dragon armor but it is usually a rare drop.
Shaman and Hunters can wear mail when they reach level 40 and train at the trainer for it. Paladins and Warriors start out as wearing mail, but at 40, turn to plate armor. Death Knights start in plate armor, but can wear mail, although, probably shouldnt, it would be a downgrade. Mage, warlock, priest, druids, rogues can never wear mail armor.
Death Knight don't wear "DK Armor", they can wear anything from cloth to plate. In a DK's first 4-6 levels you can get armor and weapons that no one else can get because they are rewards for DK only quests. If the other plate wearing classes could get it, they also could wear the armor.
For a Paladin to be able to wear plate armor, they need to train for it at their trainer when they reach level 40. Before level 40, they can not wear plate.
Chinese warriors sometimes have a mustache, wear a piece of armor, ties their hair up and never washes their hair
You just need to learn it from your proffession trainer. Warriors and Paladins can learn plate at level 40 Shamans and Hunters can learn mail at level 40 No other classes can learn any other armor types than the one they start with.
chainmail armor helmet chest plate gauntlets footwear