There has been number of communication methods available since the start of human civilization. Post mail (snail mail) was there for decades as the primary long distance communication mechanism. As technology evolve the mail had to be faster than the snail mail. So Electronic mail (eMail) came in to place.
An eMail address
An email address contains several main parts.
This is the first part of the email address, and this makes the email address unique & personalize.
@ (At Sign)
This separates the Username part from the Host Name section.
This part represent the company or the email service provider.
This separates the Host Name from the Top Level Domain.
Top Level Domain
This is the end part of an email address, This part represent what type of company it is or where the server is located.