Islam is a religion of peace. This is evident even from the name "Islam" itself. ("Islam" is an Arabic word.) The word "Islam" and the Arabic word for peace, "salam" both come from the same root, "salima".
Muslims are taught to greet each other by saying "salamun alaykum--peace be upon you." The daily prayers also end with the same sentence. In Islam, one of the names by which God is known is "Salam" which means peace.
However, one must realize that peace can never be achieved in vacuum. It is intertwined with justice. One can have peace only on basis of justice. "Justice" means putting everything in its rightful place. If one starts putting things in the wrong places, then he disrupts the social harmony and disturbs peace.
Islam seeks to promote peace on two levels:
1. Peace within One's Self:
A person can achieve inner peace by creating harmony and balance between his main emotions (desire and anger) and his spiritual self. In other words, between his emotions and his conscience.
Human's spiritual power or conscience is not a static phenomenon: it has the ability of growth as well as decadence. God swears by the soul of human being and says, "He inspired to it to understand what is good and what is evil. Prosperous in the person who purifies it, and failed is he who seduces it." (Qur'an; chp. 91, verse 10).
2. Peace With Others:
Islam very strongly emphasizes on the rights which people have over each other. It seeks to perserve peace in society by training and urging its followers to fulfill the rights of each other. In Islam, salvation is not possible by just fulfilling the rights of God; one has to fulfill the rights of other human beings also.
Unfortnately, because of the Middle Eastern events of the last three decades, Islam has been branded by the media as a religion of violence. In recent years, the word "Islamic" has become one of the adjectives of "terrorism." In this backdrop, firstly, one must realize that the events in the Middle East can be fairly and fully understood only in the light of the post-WWI history of that region, in particular the promises given by the British to the Arabs. Secondly, no fair-minded person would allow himself to blame the religion of Islam for the wrong-doings of those who call themselves as Muslims. It is just like saying that the Catholic Church promotes violence and terrorism because of the Irish Republican Army's activites!