Answer:
I am longer than a decade and shorter than a millennium
You find me behind the stars; or in a sixth seventh or third. It takes something round a computer and me to make pie. I am bigger than anything you can think of.
I am a portal to another world which you cannot enter. Only you can see me but I can't see you.
I cover what's real; hide what is true, but sometimes bring out the courage in you. What am I?
I am owned by every man though my length differs. Their wives uses me after getting married.
When is it bad luck to see a black cat?
What am I?
Animal
Difficult
Easy
Food
Funny
Kids
Logic