GuildWiki has been locked down: anonymous editing and account creation are disabled. Current registered users are unaffected. Leave any comments on the Community Portal.
The Skill Bar contains all your currently equipped Skills.
The Skill Bar has 8 slots. According to the official explanation this is because "most skills come in the form of a ring to be worn on the character's finger, which is why one can take only 8 skills into battle."
To execute one of the equipped Skills you can click on its icon or press its corresponding key. Skills are always numbered 1 to 8 on the keyboard, unless you change their shortcuts (in this case, the numbers disappear).
Some skills will require you select a specific target before execution: either an ally, a foe, a pet or a spirit. Offensive skills and attacks may automatically select a valid target if one wasn't selected manually, as long as there is one available and Auto-Targetting is not disabled in the General Options panel (F11).