Computing - Electrical Communication

E-mail (Electronic Mail

E-mail is the process of sending information electronically between computers.
Users are identified by e-mail addresses to send and receive e-mails. Example of e-mail addresses include: [email protected] and [email protected].

Attachments

A basic e-mail is a simple text message. However, users often wish to send files along with e-mails. An attachment is a file that is sent along with an e-mail message.
Attachments can be word processing documents, graphics or even programs. Attachments can be used to do things like send photographs or share music files with friends.

Advantages:

• E-mails arrive almost instantly while the post can take several days.
• E-mails do not incur the expense of stamps.
• The same e-mail can be sent at once to a group of people in an address book.

Disadvantages:

• E-mails can include viruses that do damage to computer systems.
• E-mails can only be sent to people who have e-mail addresses.

Netiquette

Netiquette is the name given to the rules of good behaviour when sending e-mails. Netiquette is a shorthand way of saying 'network etiquette'.
There are many rules of netiquette which can be found on the internet by entering:
"netiquette" into any search engine. A few of the more important rules are given below.

• E-MAILS SHOULD NOT CONSIST ENTIRELY OF CAPITAL LETTERS. THIS IS CALLED 'SHOUTING'.
• E-mails should not be sent if they contain angry or inflaming remarks such as "Try to do better next time or you are fired". Sending such e-mails is called flaming.
• Sending junk e-mails is not good manners. This is called spamming.
• E0mails should not be too formal. Unlike a conventional letter you are not expected to use terms such as 'Dear Sir' or 'Yours Sincerely'.
• Don't waste other people's time. For example, repeatedly sending funny stories downloaded from the internet or messages are unnecessarily length wastes time.

Text Messaging

Devices such as mobile phones and palmtop computers can send text messages to each other.
SMS (Short Messaging Service) is a system used to send text messages between mobile phones. Most mobile phones do not have full keyboards and so a language of abbreviations has grown to make the creation of messages quicker. For example someone might send 'C U L8R' instead of 'see you later'.

Fax

A fax machine scans a paper document and translates the picture into a code of binary numbers.
The binary numbers are then transmitted over the telephone line to another fax machine which converts the numbers back into a picture and produces a printout.
Faxes are normally used to transmit fairly small amounts of data such as orders or invoices. 

LANs and WANs

What is a Computer Network?

Stand-alone: A stand-alone computer is one which is not connected to any other computers. Nowadays most organisations and even homes don't operate with stand-alone computers but link computers together to form a computer network.
Two or more computers that have been connected so that they can share resources and communicate with each other make up a computer network.
For example, a…