What are Option Greeks?

What does the Delta of an option measure?

What is the typical range for the Delta of a call option?

What does a Delta of 0.5 signify for a call option?

Why can't the Delta of a call option be greater than 1?

What is the approximate Delta value for a deep in-the-money call option?

What does a negative Delta value indicate for a put option?

Who or what determines the value of the Delta for an option?