Here are some of the key terms of Islam along with some basic definitions.
Islam-submission to Allah
Muslim-one who submits to Allah
Qur'an-"the recitation", Scripture of Islam
Allah-Arabic name for God
Muhammad-chief prophet of Islam
Hadith-teaching of Muhammad
Surah-chapter of the Qur'an
Sunni-largest group in Islam
Shiite-second largest sect of Islam
Ayatollah-spiritual leader (Shiite)
Caliph-main leaders of Islam
Imam-leader
Mosque-place of worship
Mecca-birthplace of Muhammad, holiest city
Jihad-holy war
Fatwa-religious decree
Allahu Akbar-God is great
Shirk-unforgivable sin, deny oneness of Allah
Tawhid-refers to oneness of Allah
Sharia-Islamic law
Shahada-confession of Muslims, There is only one God worthy of worship and Muhammad is his prophet