Electronic mail is known as e-mail. E-mail is a simple ways to send and receive a message or letter from one person to other person. With the help of e-mail we can send a letter anywhere in the world within low cost. We can send message, letter, audio, video, graphics, any files and documents by e-mail. In technically e- mail is work on client server application. It is developed by Ray Tomlinson in 1972. E- Mail can be divided in to two portions. One is user portion which is change by user at time making the mail and second is domain portion which is fix portion and don’t change by user.
There are following e-mail benefits which are below:
1. Speed: The speed of e-mail is very high comparison to post office system. By e-mail we can send a letter in few seconds in entire the world.
2. Content: we can write a letter some line or lots of lines but expenses do not depend on weight like as post office.
3. Cost: We can send letter or a file with less money comparison as other source.
4. Easy to use: It is very easy to send letter comparison as post office system.
5. To receive message: It is not necessary that a person is on the system when we receive the message. We can open message any time whenever need it.
6. Multiple copies: We can send a file or letter to lots of person at same time without write other letter.
There are following e-mail demerits which are below:
1. Need to Hardware: Without hardware we cannot send e-mail to person. Before sending e-mail we will buy hardware.
2. Need to internet: For sending e-mail we need to internet without internet we cannot send e-mail.
3. No e-mail security: whenever we send a mail to other person then it is possible to read a mail by hackers.
Structure of E-mail:
Message in an E-mail is Binary Data which is the form of ASCII that provide ability to read text of any computer. There are following part of sending mail.
To: In to we write that e-mail id whose we send a mail.
CC (Carbon Copy): We use carbon copy when we send message or mail more than people at one time. In this type mail all e-mail address are share each other.
BCC (Blind Carbon Copy): In BCC we send message or e-mail more than one person at same time but in BCC all mail address do not share each other.
The main difference between CC and BCC is the mail address are share each other in CC and don't share in BCC. Both are used to e-mail sending more than one person at same time.
Subject: In this portion we write a subject of that topic which wants to mail. By subject we know that our topic which related.
Body: In this portion we write text. We can write text according to our requirement. It means we write a message or letter in this portion.
Attachment: By help it, we can attach a file. We can attach like word document, spread sheet, image, audio, and video etc. We can attach maximum 25MB data in one Gmail. If we want to attach more data from 25 MB than we use Google drive.
Signature: It is personal information for e-mail message which is itself generated on sending message.
E-mail Protocols: Interactions between email servers and users are governed by email protocols. Some of the important email protocols are as follows:
SMTP: SMTP stands for Simple Mail Transfer Protocol. It is the protocol used in sending or outgoing emails. SMTP is the protocol is the protocol always used for sending or outgoing emails.
Unsecured Port – 25
Secured Port - 465
POP: POP stands for Post Office Protocol. It is the protocol used in receiving emails from a mail server.
POP3: It stands for Post Office Protocol version 3. It is a standard mail protocol used to receive emails from a remote server to a local email client. POP3 allows us to download email messages on our local computer and read them even when we are offline.
Unsecured Port – 110
Secured Port - 995
IMAP: It stands for Internet Message Access Protocol. It is same as POP because it is used in receiving email from a mail server. It is standard protocol and has secure connections.
Unsecured Port – 143
Secured Port – 993s