Email is vitally important basically for mail transmission electronically among people in the world of globalization in the field of modern technology. There are also innumerable mailboxes, mail servers and other features like those in traditional post office systems. Only the difference is the simplicity and speed in the information transmission via computer and Internet. E-mail is a vast accomplishment in the world of communication. It is a great attainment because it allows messages reach its recipients within a very short time. If anybody asks how much time it would take for a letter to reach Bangladesh from EU or USA, even the top officials of the Post department would not be able to react. The fastest mail delivery system of the world, DHL takes a minimum of three days to deliver mail to a client. There are of course other communication devices like phone, fax, telex, but often those are too costly. Among all the media of information transmission, email is the best as it is the cheapest and also the fastest. Also it ensures privacy or confidentiality, as the message is stored in the mailbox of the recipient directly. The sender can be sure that the recipient will obtain the message, which is sometimes impossible to assume in case of Fax. Another great benefit of email is that a user can access his/her messages from any computer of the world that has Internet access, whenever he/she wants to check for e-mail.
Every email recipient must have an email address to be identified and to temporarily store the message in the mail server. If there is no address, how you will be able to locate any person among millions of people. You must have an address, and so email is sent to addresses. Example: alam@bangla.net is an email address. Every address must be specified according to the mail server. The unique name before the @ sign would give the identification of the recipient. Here alam is the user or recipient and bangla.net is the mail server. Email works like a postal system. When someone mails a message (letter), first it is stored in a mail server. This is just like posting the letters in the local post office or letterbox. Mail servers are the storage points like the postal department’s post offices, which act as temporary storage during transfer of letters from sender to receiver. In case of electronic mail, mail servers serve as the sender’s post office; the e-mails are then forwarded to numerous other mail servers before it reaches the recipient’s mail server. The sender’s mail server also plays important role in controlling data traffic. When in any network junction there are jams, then server stores some messages and sends the messages after the network gets free. In this way it protects the traffic jams in the message paths. Besides, there are a different email system, which acts as gateways or translators among POP3 or X.400.
When the message reaches the destination mail-server, it is stored there until the recipient checks for it and receives it.
In view of the above it is evident that if someone has an account or user permission he/she can enter into his/her ISP’s Internet Server, through which he/she can access any Internet Server in the world. Any person can browse through any information from millions of computers after he/she enters an Internet server. For this reason, Internet is a great wonder of modern science, the so-called information super highway. A web-site is a hard disk space in one of the billions of computers in the Internet. A certain web-site will have information on a specific topic. For example Education, Sports, Shopping, Business or any other topic will have several web-sites dedicated to those topics. We can get the news from web-sites of CNN or BBC. A web-site is identified on the Internet by a unique address.
