The Arabic word 'Islam' simply means 'submission', and derives from a word meaning 'peace'. In a religious context it means complete submission to the will of God. 'Mohammedanism' is thus a misnomer because it suggests that Muslims worship Muhammad (SAW) rather than God. 'Allah' is the Arabic name for God, which is used by Arab Muslims and Christians alike.
"When a person dies, his works end, except for three: ongoing charity, knowledge that is benefited from, and a righteous child who prays for him."
Prophet Mohammed (PBUH)
"The best of what a man leaves behind are three: a righteous child who supplicates for him, ongoing charity the reward of which reaches him, and knowledge that is acted upon after him."
Sunan Ibn Mājah
"Every day two angels come down from Heaven and one of them says, 'O Allah! Compensate every person who spends in Your Cause,' and the other (angel) says, 'O Allah! Destroy every miser.'"
Sahih Bukhari