Internet Security

How to avoid virus or spyware infection?

New viruses, spyware and worms are emerging every day looking their way into your Windows PC. Windows is the most popular operating system used today, thus most virus producers focus on that system.

1. Beware of the email. Email messages are the most common way of getting a virus. Most of the time, you are safe to open emails, but remember to never, ever click any link in that message, no matter how much tempting it may look like. You may only click links in messages that you've verified are 100% from genuine sources.

You also want to check if the URL leads you where it says: hover your mouse over the link and the status bar will show you the actual URL address you are going to visit if you click that link. If the link isn't consistent with the URL, be assured you are being scammed.


2. Sometimes while you work, a strange pop-up window may come up on the screen informing you that a virus has been found on your system and you need to click it to resolve the problem. Don't even think about doing it. Crackers and cybercriminals have found ways to display such messages remotely on poorly secured Windows systems and they simply want to scam you into doing something evil to your computer. Clicking that window may result in deleting all your disk files or installing highly dangerous spyware that may be used to track your online activity or to turn your computer into a zombie (which may be used to conduct online crime, such as Massive Denial of Service Attacks).


3. Be careful when dealing with instant messaging. Instant messengers are often used by criminals to send spam, and scam messages that can also contain viruses. Remember to never open any file, may it be sound, video, picture or text, if the message they are in is not from your buddy.

Some documents, including video files, can be really dangerous. Crackers have already discovered ways to smuggle viruses using video files, so be careful before opening any of these.


4. Don't download any files from any dubious website. If you are suspecting the site you are visiting may not be 100% legitimate or you are visiting a site that is not well-known to be safe, refrain from downloading any software. Don't download any documents, may it be executable file, Word file or any other file. All of them may be a virus.

Hypermedia & Hypertext

Hypertext

*Hypertext is basically the same as regular text - it can be stored, read, searched, or edited.

*hypertext is text with pointers to other text.

*The browsers let you deal with the pointers in a transparent way -- select the pointer, and you are presented with the text that is pointed to.
Hypermedia.

Hypertext, made famous by the World Wide Web, is most simply a way of constructing documents that reference other documents. Within a hypertext document, a block of text can be tagged as a hypertext link pointing to another document.When viewed with a hypertext browser, the link can be activated to view the other document.Hypertext documents can either be static (prepared and stored in advance) or dynamic (continually changing in response to user input). Static hypertext can be used to cross-reference collections of data in documents, software applications, or books on CDs.

A good characteristics of good hypertext consists of:

-lots of documents
-lots of links
-range of details
-correct links

Example of hypertext.
http://www.edwebproject.org/hyper4.html


Hypermedia

*Hypermedia is a superset of hypertext.

*Hypermedia documents contain links not only to other pieces of text, but also to other forms of media - sounds, images, and movies.

*Images themselves can be selected to link to sounds or documents.

*This means that browsers might not display a text file, but might display images or sound or animations.

*Hypermedia simply combines hypertext and multimedia

Examples of hypermedia.
http://www.iicm.tu-graz.ac.at/hwbook/22/22.11/node351.html

what are web blogs?

Weblogs

A blog is a website in which journal entries are posted on a regular basis and typically displayed in reverse chronological order. The term blog is a shortened form of weblog or web log.Term “weblog” coined in 1997 by Jorn Barger then shortened to “blog” by Peter Merholz in 1999. blogs have been popular since 2001 until now from the "Baghdad Blogger".

Merriam-Webster Online Dictionary defines a blog as a

“website that contains an online personal journal with reflections, comments and often hyperlinks provided by the writer.

Wikipedia goes on to talk about the range of blogs from “individual diaries to arms of political campaigns, media programs, and corporations”.

Terminology :

Blogger – person who maintains a blog
Blogging – the act of creating a blog

Blogrolling – moving form blog to blog
Blogrolodex – a listing of other blogs
Blawgs, Klogs, Trackback, Ping, Permalink, …


Formore example of blogs.

http://www.elearnspace.org/blog
http://www.downes.ca