The alignment of a player is a cumulative representation of how good or how evil that player is. Your alignment is affected by the alignment of the monsters you kill, and certain objects on the mud. The alignment of a monster is set upon its creation, and generally does not change.
There are several guilds upon EotL in which alignment plays a major part. Alignment can also influence the armor you can wear, weapons you can wield, and even the areas you can enter.
Your alignment is a number, represented by the following scale:
Angelic Saintly Very Good Good Honorable - Neutral - Evil Very Evil Devilish Demonic
You may display your current alignment with the score command.