1)
The number one ingredient for a
catastrophic event in which the universe enfolds and collapses on itself and
life as we know it ceases to exist.
2) A mathematical equation such as a/0 whereas a is some number and 0 is the divisor. Look it up on Wikipedia or something. Pretty confusing shit.
3) A reason for an error in programming
Hey, I divided by zero! ...
Oh shi-
a/0
Run-time
error: '11':
Division by zero