Combat classes

The three combat classes of RuneScape are the warrior, ranger, and mage. 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: Your combat class also affects your Combat level, because in addition to Defence, Hitpoints, and Prayer, the skills listed above for your combat class also contribute to your combat level.
 * 1/3 of your Attack level + Strength level = Warrior
 * 1/2 of your Ranged level = Ranger
 * 1/2 of your Magic level = Mage
 * 1/2 of your Prayer level = Monk

Warrior
A warrior uses the Melee combat style and is strong against rangers but usually 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 magical attacks. One advantage of being a warrior is that while arrows and runes will eventually run out, a melee weapon doesn't "run out" (unless it degrades like Barrows equipment). Warriors are also melee, meaning they fight close-up and need to travel a certain distance before they can attack. Their heavy armour adds to their weight, limiting their running distance. However, this by no means implies that warriors are stronger or superior to rangers or mages. Against mages, their metal armour amplifies the power and accuracy of magical attacks.

Ranger
An archer or ranger 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. Rangers often have a hard time penetrating the metal armour worn by warriors but hit through a mage's robes with ease. Rangers are tough to take down and more mobile than warriors and their armour provides substantial defence against magical attacks.

Mage
A mage 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, but rather their potent array of spells. To cast spells, mages use runes, magical forces and energy encapsulated in sacred stones created from limited amounts of rune essence. Melee attacks and ranged projectiles often have little difficulty piercing a mage's robes. However, mages are usually lightweight compared to both warriors and rangers, and have access to a variety of non-damage dealing spells such as Bind and Curse. Mages should bind warriors and take advantage of their distance when fighting. A sharp blade is highly lethal when close up.

Monk
A monk, like a mage, typically dresses in robes to enhance their prayer capabilities. Prayer bonuses increases the amount and duration of prayer boosts. Instead of spells, a monk has access to a variety of prayers. As such, a monk specialises in protection prayers to counter a particular combat class especially during PvM combat as it negates 100% of the damage. Monks typically wields a melee weapon such as a mace and have low base defensive capabilities.