(Nafs al Ammarra). 'The self which commands'. The Qur'an refers to this self, "The (human) soul is certainly prone to evil" (12:53). This self resides in the world of the senses and is dominated by earthly desires and passions. The initial struggle in the early stages of the spiritual journey is against the Commanding Self. Nafs al Ammara is equated with the first islam and the first standing posture of the ritual prayer. The Commanding Self is journeying to Allah.
Islam means peace and the person who follows this peace is called the Muslim. From another root meaning of the word, Islam means complete submission and surrender, and the person who submits and surrenders himself to the will of his Lord is the person who has accepted Allah as his Creator, Sustainer, Lord and the Master of the Day of Judgement.
So from both the definitions Islam means a way of life for people who have opted to follow peace as opposed to chaos, order as opposed to disorder, discipline as opposed to indiscipline, submission as opposed to refusal, surrender as opposed to insolence, obedience as opposed to disobedience etc. All these things combined together to define Islam as away of life by which a person becomes a follower of peace and not a follower of chaos. And the followers of peace are the Muslims whose duty it is: "to establish peace and what is good, and to prevent chaos and what is evil, and they are the best people." (Al-Qur'an 3:110)