• I look like a weapon if you know how to handle me (Edit)
• I am most popular than any other
• People use me often when they want to be informal
• Dirty minds see something lascivious in me
• I am loved by road trippers
• Some isolated people in the world have never seen me
• I am man-made and when I am with my friends I can enlighten you
• I have trillions of twins, but they are mostly fraternal twins
• I am indivisible but I can become something else if you mutilate me (edit)
• I am often the beginning of the end, but I am not the apocalypse

What am I?