Email Concepts
Electronic Mail(Most popular of Internet services)
Snail Mail –post office mail
Spam-- junk email
Advantages of E-mail
- Speed - The physical process of transferring E-Mail is virtually instantaneous.
- Free - The is no per-message charge when it comes to E-Mail.
- Portability - If you have a computer handy, you can dial your Provider and retrieve you
E-Mail from anywhere in the world.
- File Transfer - E-Mail can be used to transfer binary files, including executable programs,graphics, sound, and data files.
- Permanent Address - If you're always "on the go," E-Mail can give you a permanent
address. Using E-Mail, friends can always keep in touch, even if they don't have your most
recent phone number.
- You don’t have to play phone tag or make and appointment to communicate with someone.
- You don’t have to be shy using email to communicate with someone.
Disadvantages of e-mail
- Email isn’t necessarily
- It may be dificuly to express emotion using email
- You can receive too much email
- It’s possible to forge email
- Some email systems can send or receive text files only
Ways of Accessing E-Mail
How E-mail works
Understanding How E-mail Works
Email Protocols
Simple Mail Transfer Protocol (SMTP)
SMTP (TCP/IP family of protocols) describes how mail is to be delivered from
one Internet computer to another
SMTP server
- Accepts outgoing e-mail
- Takes care of sending e-mail messages in packets
Transport Agent mail program that functions behind the scenes to ensure
that messages are transported in an orderly fashion according to SMTP protocol daemon
Transport agents saves mail in a mailbox (file in which mail is stored for a particular user)
Sendmail the transport agent used by most computers (runs in
background)
Daemon the Unix term for transport agents
Mail Client a program that runs on a computer that provides and interface for the mail system
Mail Server (POP server) a program running on a host computer, that as a way station for electronic mail
Post office protocol (POP)
- A protocol used by a mail client program and a mail server program to communicate with one another
- The protocol used by mail servers to receive and store e-mail massages.
E-mail Addressing
Understanding E-Mail Addresses
Understanding e-mail addresses
An E-Mail address consists of two parts:
- user ID what the person uses to login to their Internet Provider
- domain. name of the person's Internet Provider.
Example mclark@finearts.caltech.edu
User ID is mclark,
Everything after the @ symbol is the domain. This symbol is always pronounced as, "at."
The periods separating the parts of the domain are pronounced as, "dot."
Address formal description of the user name and address used by someone on the Internet
User name @ sign name of computer (every computer on Internet has a unique name)
userid@domain
jcollege@angelfire.how.edu (no spaces in addresses)
USERID a user name, registered with a computer system, that identifies a particular account
Userid not unique, but the combination of Userid and domain must be unique
DOMAIN part of a standard Internet address that indicates the name of the computer (the part of the address after the @ character)
Sub-Domain in a standard Internet Address , one part of the domain
(separated by periods)
TOP-LEVEL DOMAIN the most general domain—last subdomain in the address
Addresses are case insensitive
Case Insensitive program, system, or operation that does not distinguish between upper-and lowercase letters
Case sensitive program, system, or operation that distinguishes between upper-and lowercase letters
Special Addresses—that you can use to get information
Postmaster userid name for the person who manages the Internet system
- postmaster@yahoo.com
- info@ domainname.com
- webmater@domainname.com
- sysadmin@domainanme.com
Components of an e-mail message
Email has three main parts –headers , message body, signature
Header (mail message) lines at the beginning of the message that contain
technical information
Common headers:
- Subject: The subject of the email
- Date: When the email was sent
(Time Internet has adopted Greenwich Mean Time (Universal Time) as a standard)
- From: The email address of sender
- To: The email address of the recipient
- Cc Additional recipient(s) of the message
Message body (actual typed text) content of the email
Signatures a group of lines that is automatically appended to the end of every message sent
Email Etiquette
Netiquette
- Choose the subject heading carefully. Make it brief, descriptive, and to the point
- It’s a good idea to include parts—but not all—of an originally message when you are writing a replay
- Check the address when you compose a message or replay to a message you’ve received
- Be careful when using humor and sarcasm
- Take time to consider what you will write
- Include a signature with all e-mail
Sending a messages means
- Filling out a header
- Typing the body of the message
Address Book a collection of names and mail addresses, maintained by a mail program
Clipboard a storage area, maintained by an operating system, used for data that is being copied and pasted from one window to another.
Sending Copies of a Message
Two types regular and blind—a secret copy that no one else knows about except the person who sent the message
Forwarding and Bouncing Mail
Forward to mail an edited copy of a mail message to another person
Bounce to mail another person an identical copy of a mail message that you received
Forwarded mail will have the greater than > character before each line of text
Bounced mail looks like it was sent by the original person
E-mail hoaxes should never be forwarded.
Hoaxes
Hoaxes
Mail Storage
Folder a collection of messages with a particular name—a file containing messages
E-mail Attachments
Text and Binary Data
Data any type of information that might be stored or processed by a computer
Two types text and binary data
- Text consists of ordinary characters—letters, numbers punctuation etc.
- Special characters as space and tab are considered text
- Data that contains ordinary characters or called text files or ASCII files
- American Standard Code for Information Interchange (ASCII) a specification that defines how all the various characters are represented as computer data
- Binary data a file that contains data that is not plain text and must be interpreted by a program to make sense
- A file that contains a picture , word processing or a spread sheet is a binary file
- Binary file stores the data in binary format (series of dots) that is used to recreate the image
- Each dot is encoded as one of two numbers—0 or 1
- O represents a white dot 1 represents a black dot
- Elements that contain one or two values—0 or 1 is called a bit (binary digit)
- Data that does not consist of characters and must be represented by a sequence of bits is called binary data
- Mime a special system needed to send binary data (best method to send attachments)
Using Mime to Mail Binary Data
Multipurpose Internet Mail Extensions (Mime) a protocol used to send binary data
Attachment A file that is joined to a mail message so that the file is delivered along with the message
- Mail program encodes the information in the file as textual characters
- Uuencode (Unix) a system used to encode binary data a ASCII text (oldest)
- Uudecode (Unix) a system used to convert data back to its original binary format
- mpack and mupack used to send and receive Mime-encoded files
Practicing Safe Mail
- Assume there is no privacy
- Do not assume that a deleted message cannot be restored
- Be careful what you promise
- Be polite and keep your temper
- Remember that many Internet people are foreigners
Emotions icons used to indicate emotion, which is usually lacking in written communication
Smileys
Abbreviations Used in E-mail
Smiley consecutive characters that, when view sideways, look like a small face
Finding Someone's E-Mail Address
- Just Ask!
- Check an E-Mail Directory
- Look at the Return Address
- Use an Online E-Mail Search Service
Finding e-mail addresses
E-mail Guides
