26. Electronic mail: main parts and functions. Spam. Newsgroups.

Electronic mail, which has come to be known as e-mail is one of the most popular services on the Internet. E-mail allows users to send digital messages to storage areas known as mailboxes on server computers where they can be read by other users. Each user has ones own e-mail address, which determines where their e-mail is stored. A typical e-mail address might have the following components: username of identifier, @, server name, type of organization, country (e.g. locka@pesto.co.uk)*

The e-mail message has two main parts known as the header and the body of the message. The body contains the message itself, the header reveals the identity of the recipient and the sender, the date it was sent, and the subject title of the message.

The message header should include at least the following fields:

From: The e-mail address, and optionally the name of the author(s). To: The e-mail address(es), and optionally name(s) of the message's recipient(s). Subject: A brief summary of the topic of the message. Certain abbreviations are commonly used in the subject, some of which are automatically inserted by the e-mail client, including Re: ("in the matter of"), FW: (forward), FYI: (for your information), I: (information), and EOM (end of message, used at the end of the subject when the entire content of the e-mail is contained in the subject and the body remains empty).

Date: The local time and date when the message was written. Message-ID: Also an automatically generated field; used to prevent multiple delivery and for reference in In-Reply-To:.

Formatted text, spreadsheets, sound files or video files can be attached to mail messages.

One of the biggest problems in e-mailing is spam. To prevent e-mail spam, both end users and administrators of e-mail systems use various anti-spam techniques. Some of these techniques have been embedded in products, services and software to ease the burden on users and administrators. Anti-spam techniques can be broken into four broad categories: those that require actions by individuals, those that can be automated by e-mail administrators, those that can be automated by e-mail senders and those employed by researchers and law enforcement officials.

Groups of users that share a special interest can subscribe to free newsgroups on the Internet. Users subscribe by registering their e-mail addresses. Subscribers can send plain text messages to a common area on a server computer where all the newsgroup members can read them. In this way, conversations about the special interest can take place between all the members of the group. The name of the newsgroup is made up of different parts separated by dots and indicates the special area the subscribers are interested in

27. Multimedia. Hypermedia. Rich media. Hypertext. Multimedia linear and non-linear categories.

Multimedia is simply multiple forms of media integrated together. Media can be text, graphics, audio, animation, video, data, etc.

Multimedia is usually recorded and played, displayed or accessed by information content processing devices, such as computerized and electronic devices, but can also be part of a live performance.

Besides multiple types of media being integrated with one another, multimedia can also stand for interactive types of media such as video games CD ROMs that teach a foreign language, or an information Kiosk at a subway terminal. Other terms that are sometimes used for multimedia include hypermedia and rich media.

Multimedia (as an adjective) also describes electronic media devices used to store and experience multimedia content. Multimedia is similar to traditional mixed media in fine art, but with a broader scope. The term "rich media" is synonymous for interactive multimedia.

The term reach media was coined to describe a broad range of digital interactive media. Rich media can be downloadable or may be embedded in a webpage. If downloadable, it can be viewed or used offline with media players such as Real Networks' RealPlayer, Microsoft Media Player, or Apple's QuickTime, among others. The defining characteristic of rich media is that it exhibits dynamic motion. This motion may occur over time or in direct response to user interaction. Elements of rich media are increasingly used in education, in areas ranging from distance learning to web-based teaching and instructional tools.

Not surprisingly, rich media presents numerous accessibility challenges. However, rich media can be made accessible if all the elements are developed with accessibility in mind and the end product is used or viewed on accessible media players. Accessible rich media typically includes captioning, audio description, and navigation using a keyboard.

Hypermedia can be considered one particular multimedia application. The World Wide Web is a classic example of hypermedia, whereas a non-interactive cinema presentation is an example of standard multimedia due to the absence of hyperlinks. Most modern hypermedia is delivered via electronic pages from a variety of systems including Media players, web browsers, and stand-alone applications. Audio hypermedia is emerging with voice command devices and voice browsing.

Multimedia software is usually interactive, so you can choose what you want to watch, listen to or write. Hypertext means that you can click on a word and jump to another screen with more information; hypermedia is similar, but works with sounds and images (e.g. the Web).

Multimedia may be broadly divided into linear and non-linear categories. Linear active content progresses without any navigational control for the viewer such as a cinema presentation. Non-linear content offers user interactivity to control progress as used with a computer game or used in self-paced computer based training. Hypermedia is an example of non-linear content. Multimedia presentations can be live or recorded. A recorded presentation may allow interactivity via a navigation system. A live multimedia presentation may allow interactivity via an interaction with the presenter or performer.