Your attack level influences how often you hit your target successfully and can be modified through various methods, all weapons have attack bonuses, attack boosting jewellery, defenders and attack boosting potions such as an attack potion or combat potion.
Your attack level also determines what weapons you may wield. The basic melee weapons are as follows;
Bronze equipment - Level 1 Attack
Iron equipment - Level 1 Attack
Steel equipment - Level 5 Attack
Black equipment - Level 10 attack
Mithril equipment - Level 20 Attack
Adamant equipment - Level 30 Attack
Rune equipment - Level 40 Attack
Dragon equipment - Level 60 Attack
The basic melee weapons include swords, longswords, maces, battle axes, spears, scimitars, war hammers and hastae ( upon completion of barbarian training ). There are a few specific weapons for melee not included in the basic list, see below.
Granite Maul - Level 50 Attack and Strength
Abyssal whip - Level 70 Attack
Barrows equipment ( melee ) - Level 70 attack