Combat classes

The three combat classes of RuneScape are the warrior, ranger and mage, though each of these also contain a number of subclasses. They are balanced so that each class is weak to one other and strong against one other, in what is called the "combat triangle." A player's combat class is determined from that player's skills. A rough way to determine a player's combat class is to compare the following, and the highest number is your combat class: (If You are none of these, then you are a Hybrid or someone with too low of levels for these to apply.)
 * 1/3 of (your Attack level plus your Strength level) = Melee
 * 1/2 of your Ranged level = Ranger
 * 1/2 of your Magic level = Mage

Your combat class also affects your combat level, because in addition to Defence, constitution, Summoning, and Prayer, the skills listed above for your combat class also contribute to your combat level.

While it was still possible to attack others in the Wilderness, combat triangle tactics were common. The combat triangle evolved to the wilderness's other activities.

Melee
A warrior uses the Melee combat style and is strong against rangers but weak against mages. Warriors generally wear heavy, metal armour that provides excellent defence against melee and ranged attacks, but inhibits the warrior's ability to perform ranged and magic attacks.

The three sub classes for the Melee combat style are Berserker, Tanker, and Warrior. The Berserker focuses primarily on their Strength and Attack to deal massive damage, at a fairly accurate rate. Warriors try to maintain a balance between their Attack, Defence, and Strength, providing them with a good array of all-around combat capabilities. Tankers train their Defence primarily so that they are not hit. It is rather redundant that they are called "tankers" however, because most melee fighters wear the same armour. Some players think training defence is stupid and call people who train it, "Def Noobs," however, this is arguable as defence is key to being able to survive in most situations, as there are few monsters that are able to be killed in 1 hit. And the Bandos godsword's special attack renders players with 1 Defence very weak.

Warriors are generally better than mages or rangers in most activities, as it does not require much long-distance fighting, and there is not very much cover for mages/rangers to hide behind.(mages can make their own cover though.)

Ranger
A ranger, sometimes called an archer (if using bow and arrows), uses the Ranged combat style and is strong against mages but weak against warriors. Rangers generally wear armour made from animal hide, and they use weapons that can hit from a distance. Updates to Ranged allow a ranger to also wear a Shield while attacking with a Crossbow, giving the ranger a potentially significant armour boost.

Sub classes include long bow, short bow, and crossbow rangers, depending on whether the player wants distance, speed, or power, respectively. Others may choose to use a thrown weapon, like a throwing knife, dart, throwing axe or javelin.

Arguably, they are the strongest class in the game, capable of producing the maximum hit of 2000.

Mage
A mage, or sorcerer, uses the Magic combat style and is strong against warriors but weak against rangers. Mages generally wear robes for armour and wield staves for weapons. However, robes and a staff aren't what make a mage powerful, rather their potent array of spells. To cast spells, mages use runes; stones that are magically-energised.

The mage combat class is further divided into two subclasses: the Ancient Mage, user of Ancient Magicks, and the Wizard, user of modern magics, for combat related activities. Lunar Mages also exist, utilising the Lunar Magicks; however, the Lunar spellbook, as detailed below, is oriented towards non-combat activities. Players using the modern magic spell book have general spells for reducing a foes combat skills, temporarily binding an opponent to a square, and doing damage and teleports. Players who use the ancient spells are looking to counter-act all players instincts to run. Note that you have to complete the Desert Treasure quest before you can use the Ancient Magicks spell book.

Mages are considered the best class for the activity Fist of Guthix, because they can bind the target, preventing them from escaping (the whole point of the activity). Also, because stats are reduced, all attacks become slightly more potent, allowing mages to hit through armour like dragonhide which is usually spell-proof. All runes used in Fist of Guthix are provided inside the activity.

Lunar Spells do not have any direct damage spells, but certain spells can be useful in combat. The cure spells instantly cure poison, and while they don't give a temporary immunity to poison like antipoison potions do, they are great if you've just beaten or ran away from a poisonous opponent. The heal spells are made for groups. Using heal spells, you can give a friend a lot of health without them having to eat food. Vengeance is a popular spell for combat, as it rebounds up to 75% of damage received in a hit onto an opponent, without interrupting a hit of the player with vengeance. If you have the Lunar Spellbook it is useful for Meleers and Rangers as you can heal and cure yourself and others useful for all combat classes. Magic can also be useful for other combat classes as with higher Magic Levels you have more resistance to Magic damage.

Trivia

 * Monks or Priests using the prayer skill are sometimes said to be a combat class.