The basic theory is that killing someone who in your racial pairing will result in a loss
The alignment system is the main mechanic that determines if you are in good standing or bad standing (red) with members of your own racial pairing. The basic theory is that killing someone who in your racial pairing (who isn’t red) will result Runescape Gold in a loss of alignment and brings you closer to being red, while killing the natural enemies of your race and red players will increase your standing.
The value of a negative hit is much higher than that of a positive one, so it will take several enemy kills to negate the effects of a single friendly kill. If you only hit another player, will be rogue flagged for a short period of time, in which case you can be killed by friendly targets as a means of self-defense.
Your alignment is displayed as the bottom meter in the window where your life, stamina, and mana are located.
Having a bad alignment and going red does have some consequences. Besides the obvious of being a target to everyone in the game, your own racial towns will not welcome you and you will be attacked by the guard towers.
You will also not be allowed to bind at the same bind-stone as normal players, which makes sense because since the bind-stones are in town, you would be attacked immediately.