I was just wondering how paypal really works?

It's free but it has a fee when having transactions right?
Is it really safe?
Where can you see if you've received a payment? And how would you know who payed it?
Is there a specific bank that you need to have an account?

if there's any other info you could share, i would really appreciate it

also, anyone know xoom.com? is it recommendable?

i know some of my questions are already answered in the paypal site, but I just want to hear from the people who has it first hand..just to be sure and so that i won't misunderstood some things xp..

thanks for reading! ^^

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