Question : Internet Fax services

I have seen many companies that provide Internet fax services.
I would like to know why would you go for a company that does that? since you can have a fax server scan a document in the fax machine send it to the share or to your email and you can email it.
what do the internet fax service provide more? and what is the Virtual Fax Service
that also some companies provide?

Thanks

Answer : Internet Fax services

If you're using a fax service and you send an email to the service for transmission as a fax, the service will try multiple times (like a normal fax machine will) to send the fax. After a certain number of times, it would register a failure, and you would receive a notification of that failure, but you'd have to look at a particular service to see the details of exactly how that's handled. (I think all of them provide an email notification of success or failure; some may also offer notification by text message to your cell phone.)