What is difference in Using a UK and US Shopify Address?

Hi guys,

Can anyone explain what the difference is between using either address. Am i correct in saying if i use a UK address, i can only dropship to UK?

This relates to this - https://ecommerce.shopify.com/c/shopify-discussion/t/how-to-sell-to-the-us-from-the-uk-433667

PS - A newbie here on shopify

Thanks