What is a post hoc fallacy?

It's the fallacy of stating or thinking that if 'B' came after 'A', then 'A' must have caused 'B'.

Here's a ridiculous example:

Every day at 4:00 in the morning, I rub this gold ring that I always carry
in my pocket, and every day, within two or three hours, the sun rises. 

This has been happening regularly, for almost five years now, so I know
that I can totally rely on it..

I'm getting ready to write to my Congressman and tell him that if he does not
send me five million dollars within a week, I will not rub the ring for a week, and
that will cause havoc with farming, transportation, and weather, since the sun
will not rise for a week.