Do Christians and Muslims worship the same God? Anyone with a basic understanding of both religions should answer "no", yet there are many in this world who say "yes". You can prove this assertion false with one basic question: Do you worship Jesus? Ask a Muslim, they will say no, of course not! That's shirk, and a ticket to eternal damnation. Ask a Christian, they will say yes, of course, that is literally the only way to avoid eternal damnation!
In Islam, saying Jesus is God is shirk, the greatest sin. Thus, Christians have three choices: Convert, pay the Jizyah (a sort of religious "tax" acknowledging the inferiority of your beliefs), or die. In Christianity, by contrast, acknowledging Jesus as Lord is the only way to be saved. You must confess Jesus as Lord, and believe in your heart God raised Him from the dead, both of which are conclusions that are intolerable in Islam.
This is so unbelievably basic that I am surprised I managed to stretch this particular article into three paragraphs. Yet, so many people fall for it. Atheists claim Christians and Muslims worship the same God, Muhammad initially claimed Christians and Muslims worship the same God, various Christian groups and individuals claim Christians and Muslims worship the same God, this utter lie is spread so far and wide, it seems if you throw a stone in a city, it will hit some silly goon who believes it. If so many people lack basic knowledge, to the extent where two obviously distinct beings can be classed as one, it's no wonder this world is still in rebellion against God.