Islam comes from the root word “sa-la-ma”. The root word symbolizes peace, security, safety as it does to submission to the will of God. Peace and security become inherent to the one that submits to the will of God, achieving a sense of tranquility and satisfaction.
Islam has been the religion of all prophets, from the first Adam (AS) to the seal of the prophets, Muhammad (SAW).
Indeed, the religion in the sight of Allah is Islam. And those who were given the Scripture did not differ except after knowledge had come to them – out of jealous animosity between themselves. And whoever disbelieves in the verses of Allah , then indeed, Allah is swift in [taking] account.
Sura Al-Imran 3:19
To get a more detailed description of Islam, the following links may be used: