What is underwriting? Any help and advice appreciated!

[teaga]

What is underwriting? First of all let me explain why I need to know�I'm putting on a event and the event management company I am using to organise things said they can find a sponsor for the event to raise the initial funds needed, however they said you will also need to have and underwriter cover expenses. What exactly is underwriting, what's it for, is it like an insurance policy if the worst happens??? How much would it cost and how do they get paid? What would it cover? Do they take into consideration personal finances or credit history or is it based on a business plan etc? Do you know of any reputable companies that I could use? I know it's a bit vague and probably some stupid questions listed, but I've never come across this before. Please help, any advice would be much appreciated. Thanks