system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5:Escrow

I'm about to buy a house, and I don't totally understand Escrow.
What is it?
How is it used?
Why is it important?
gpt
Imagine you want to buy a baseball for $5 from Bobby. Normally it'd be fine, you'd just hand him $5 and he'd give you the ball. But you only get $1 in allowance each week. So you need five weeks to get the money together. 

Bobby doesn't want to just give you the ball, but you're also worried Bobby will lose/damage/sell the ball in the meantime.
So both of you go to Rebecca and say "hold on to the ball, and each week Rhysic will give you $1. At the end of five weeks, give him the ball and Bobby the money."

Rebecca is holding the ball and money in an escrow account.