Question about computers?? please read and answer!!!!?

okay...this might be a weird question but if someone could answer that would be great.

If you email someone from 2 different computers do they know? Like how can you read the modem number? When you send an email do they know what the number is. I know there is some type of number your computer has, and some websites know it when you join. I just don't understand if just a normal person emailing through like yahoo or aol would know what your number is. Sorry if this is confusing!

Thanks

Question about computers?? please read and answer!!!!?spyware

As far as I understand, no one will be able to find out whether the e mail is sent from two different computers. There are many cyber cafes and you can log on to your e mail (or website) from different cyber cafe at different time and also send e mails.

Question about computers?? please read and answer!!!!?virus scan

Yes.. You can get that information by opening the email properties in outlook express. It will tell both ISP number, the from and to parties involved. Right click on the email choose properties.

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