Email works in a similar fashion to regular mail, only it's much faster. A sender first creates an email (letter) and addresses it to a user. The address is of the following form - userid@company.com. The userid is the name (or an alias) of the recipient. The company.com (or any other domain suffix) represents the organization to which the company is being directed. The company also hosts the user mailbox from which the emails are retrieved and sent.

The email is first sent to a service provider (post office). Based on the address, the routing for the letter is computed and the letter is then routed through several routing centers. When the email reaches its destination, it is deposited into a mailbox. The recipient then retrieves the email from his/her mailbox and can read it.

Contrary to popular belief, emails are not a secure form of communication. Email has the same amount of security as a traditional postcard. Using a readily available piece of software called a packet sniffer, email can be intercepted and read at will. Thus, you should never transmit confidential information such as credit card information, passwords, or health information via email.