About e-mail

E-mail is often called the killer application of the Internet. However,it actually predates the Internet and was a crucial tool in creating it. E-mail started in 1965 as a way for multiple users of a time-sharing mainframe computer to communicate.
In 1971 Ray Tomlinson created what was to become the standard Internet e-mail address format,using the @ sign to separate user names from host names.
Now let me to introduce some familiar email host web to you.

Yahoo!Mail is a free email service offered by the American search engine company Yahoo! Yahoo!Mail was the second largest web-based email service with 310 million user as of October 2011,and the most popular web mail service in the United States.

Gmail is a free,advertising-supported email provided by Google.Users may access Gmail as secure web mail,as well as via POP3 or IMAP4 protocols.

Hotmail(officially Microsoft Hotmail,previously Windows Live Hotmail and MSN Hotmail) is a free web-based email service operated by Microsoft as part of Windows Live. One of the first web-based email services, it was founded by Sabber Bhatia and Jack Smith and lauched in July 1996 as 'Hotmail'.

Reference: http://en.wikipedia.org/wiki/History_of_the_Internet#E-mail_and_Usenet

http://en.wikipedia.org/wiki/Yahoo!_Mail#History

http://en.wikipedia.org/wiki/Gmail

http://en.wikipedia.org/wiki/Hotmail

Some of my feelings for such web mails:
The Gmai service currently provides more than 10 GB of free storage per account. Users can rent additional storage from 25 GB(US$2.49/month) to 16 TB(US$799.99/month). But actually it is no use to me because i just use mail to receive and send email,maybe this is useful to businessman.The features of Yahoo!Mail are similar to Gmail,but the ability of preventing spam is worse than Gmail. On the contrary, Hotmail's security is better,Hotmail will not only  scan for virus, but also warn users if their mailbox have  untrusted mail.