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Instant Messaging

An instant messaging program notifies you when your friends are online. Then you can send them messages, which they see immediately. Only the one you send the message to can see it and only you can see the messages that are sent to you,  unless you choose to change to a multiple-user mode.

Recent versions of instant messaging include the ability to use video conferencing, to play games together with your friends, and even to make phone calls over the Internet. Examples of instant messaging programs are ICQ, AOL Instant Messenger, Yahoo! Messenger, Google Talk, Facebook, and Windows Live Messenger.

The image below shows what such messages look like in a chat in Facebook. You type your next comment in the text box at the bottom. The Facebook profile picture for the person 'talking' shows at the left.

 

Instant messaging in Facebook

Applications: Browser

An Internet browser is a program that lets you navigate the World Wide Web or view HTML pages on a CD or DVD or on your hard disk. [It's likely to be what you are using to view this page if you are reading this on a computer!]

A browser displays web pages, keeps track of where you've been, and remembers the places you want to return to.

More information is available over the Internet every day, and more tasks can be done. You can buy books, check on your bank account, buy and sell stocks, even order pizza over the Internet. But you have to have a browser to do it.

Internet Explorer

Google Chrome

Internet Explorer may no longer be the most popular browser [June 2012]. Mozilla FireFox has evolved from the original favorite browser, Netscape, and has become the favorite of many. But, Google's Chrome is gaining market share and may have passed IE. Safari is the browser that comes with Apple computers.

Browsers that are built into devices such as smart phones and tablets may be unique to the manufacturer or they may be simplified versions of PC browsers.

Modern browsers include many of the same features, such as tabs instead of separate windows to make it easy to move between several open pages, a list of previously viewed pages (History), a list of places you want to be able to get back to (Favorites or Bookmarks), the ability to install add-in programs to view videos in various formats or to interact with web pages.

Purpose:

  • Navigating the Internet

Major Advantage:

  • Can display graphics, which older internet applications didn't

  • Keeps a list of places you want to return to.

  • Shows HTML pages, which can include links to other pages and files for quick access.

Which is the most popular?

Which browsers are most popular changes over time. No one can actually count all of the visits to web sites! All of the numbers are estimates based on just a part of what is really happening in the world.

The numbers you hear about depend on:

  • Equipment used to browse: desktop computer or a mobile device (Different browsers available!)

  • Number of sites being counted (one, a few thousand, hundreds of thousands, millions)

  • Location of the sites being counted (in one region, one country, or scattered around the world)

  • Type of sites included (mostly similar or widely different; technology, social, business, government, education, sales)

The numbers below are from three different source, including two that news headlines about browser wars seem to use most often, NetMarketShare and StatsCounter.

NetMarketShare stats:

The images below show the statistics from the network of 40,000 sites that are HitsLink Analytics and SharePost clients. That sounds like a lot of sites, but the Internet has millions!

The market share on the desktop computers for Microsoft Internet Explorer dropped 6% while Google Chrome's share went up 7.27%. Netscape used to be the dominant browser and is now less than 1% of users! Now that's a fall!

For mobile computers like smart phones and tablets, the dominant browser has clearly been Safari, but its market share is dropping. Android is gaining.

More statisitics: NetMarketShare: HitsLink.com:Desktop Browsers HitsLink.com: Mobile/Tablet Browsers

StatCounter Global Stats

StatCounter Global Stats gets their statistics from the log files of the sites of its more than 3 million members, who uses StatCounter to analyze data about visitors to their web sites. There were 18 billion page views in January 2012. That's a lot of data!

The graph below shows that world-wide Chrome overtook Internet Explorer in May 2012, but in the USA the numbers are different.

More statistics, including mobile browsers: Stat Counter

W3School.com statistics - single site:

These statistics are only for visitors to the W3Schools site, which is a resource for people who are writing web pages. So the visitors to their pages are more likely to be in the "techie" group of browser users - and are probably picky about their browser, too! Quite a difference in which browsers are popular! What the 'techie' people favor tends to become popular with the general population after a while, but not always.

The site did not have charts, so I took the numbers from their site for May, 2012, and made a pie chart. Quite different from the pie chart for NetMarket Share!

 

Internet Explorer

Firefox

Chrome

Safari

Opera

May 2012

18.1 %

35.2 %

39.3 %

4.3 %

2.2 %

Sept. 2011

22.9 %

39.7 %

30.5 %

4.0 %

2.2 %

Sept. 2010

31.1 %

45.1 %

17.3 %

3.7 %

2.2 %

For more statistics, including mobile browsers: w3schools.com stats

For more on using a browser, see the section Working with the Web: Browser Basics

Applications: Web Pages

To create a web page for the Internet, you must write HTML (Hypertext Markup Language) code to define what is on the page, create or acquire the images for the page, and then upload the files to a web server.

What do you need?

  • HTML editing program

  • Graphics editing program

  • Uploading program

  • Browser

  • Web space

HTML Editor: You can use any plain text editor, like Notepad, to write the code. Or, you can use a specialty program for writing HTML pages. Such programs make it much easier to manage complex pages and large web sites. Also useful are programs that help you write scripts or that check your HTML code for errors.

Popular programs for writing HTML include Notepad (write the code yourself!), Microsoft Expression Web, and Adobe Dreamweaver.

Graphics: For the images on your web pages you need a graphics program that can save your images in GIF or JPG format. PNG format will work for newer browsers, but GIF and JPG work for all browsers.

MS Paint: Older versions of MS Paint, which comes with Windows, cannot save images in GIF, JPG or PNG formats.

Can your version? Open MS Paint (Start menu > Run > type mspaint and click OK). Look in the Save As dialog at the file types: File > Save As > File type list. If the list includes GIF, JPG, and PNG, you are ready to create and edit images for your web pages.

(If you do much with images, you will soon want a more advanced program than MSPaint!)

You might also want a scanner to scan photos and drawings. Collections of clip art come in very handy.

Uploading: To move your new web pages and images to a web server, you need uploading software, such as an FTP program. HTML editors like Expression Web and Dreamweaver include uploading as a built-in feature.

Browser: To view your web pages you need a browser, like Internet Explorer, FireFox, Google Chrome, Safari, or Opera.

Web space: You can view pages yourself that you save to your hard disk, but no one else can see them. You need access to space on a web server to share your work with others on the Web. Your ISP account, with which you connect to the Internet, may come with some web space. There are ad-based, free web hosting accounts. Or, you can purchase a web hosting account with a commercial hosting service.

HTML Code

When each logical part of a web page is marked, the browser will know how to display the contents in a way that makes sense for the particular display device and user.

Special code tags are used to mark all the parts of a web page. For example the text in an ordinary paragraph is written in between opening and closing P tags like this:

<p>This is a paragraph</p>

Example:

In the iframe below is a simple web page. Click the link below it to view the source code for the page. Can you find the tags that define the two headings and the list items? How about a simple paragraph? What does the img tag contain? What line dictates the background image?

Your browser does not support inline frames or is currently configured not to display inline frames.<br> <a href="writing_web_pages.htm" target="_blank">View example page</a>    <a href="writing_web_pages-source.htm" target="_blank">View source code</a>

View source

Do It!

A Really Simple HTML Editor *

The text area below is actually a basic WYSIWYG editor for HTML.   Formatting buttons appear when you click inside the text area. You apply HTML tags by first selecting text and then clicking one of the buttons. In the source code view, the code is packed tight into a continuous line that wraps, instead of being on separate lines for easy reading.

Select first: Be sure to select text before clicking a button to apply a tag! If the display goes crazy, refresh the browser window and start over.

  1. Click in the text area below. Buttons appear across the top and one at the bottom left.

Use the bottom left button to switch between WYSIWYG Mode (where you can see the effect of your tags) and the source code. The label on the button changes to the mode your are not in.

source

*The WYSIWYG editor above is TinyEditor , by Michael Leigeber, used under creative commons license.

  1. Type several lines of text. Include your name in the first line.  

  2. Use the ENTER key on your keyboard to start a new line. Use SHIFT + ENTER to create a line break.  

  3. Play with the various buttons until you understand what each of them does.  

  4. Apply at least two heading styles and 2 formatting choices to text that you select.  

  5. Look at your lines in both WYSIWYG and Source modes.  

Learning more

Reading and analyzing the source code for the pages you see on the Web is a good way to learn about writing web pages. You can view the source code for any page that you can view with your browser.

Try it with this page. Right click on the page (not on a link or an image. A context menu appears. Select View Source or View page source or similar command. The source code will open in a text editor or in the browser, depending on your browser. The code for this page is a lot more complex than the example above!

For a set of lessons on writing web pages, go to Working with the Web: HTML Basics

Applications: Email

Email, or electronic mail, is becoming more and more popular as people learn to communicate again with written words. For many purposes it is superior to a phone call because you don't have to catch the person in and you can get straight to the point. No time is wasted on casual conversation. It also leaves a written record to refer back to for a response or if you forget who said what. Email is superior to the traditional office memo because it uses no paper (Save the trees!!) and it can be sent to a whole list of people instantly.

An email client is the program that has to be on your computer to download and manage emails. Commonly used email client programs include Microsoft Outlook, Windows Live Mail, Mozilla Thunderbird, and Eudora.

Another way to handle email is with a web-based email account. Your email is managed entirely through web pages. Your computer needs only a browser to access email, compose new messages, and to reply to messages. HotMail from MSN, Yahoo Mail, and Gmail from Google are popular web-based email sites.

Windows Live Mail

Gmail

Purpose:

  • Transmitting messages between computer users

Major Advantage:

  • Speed

  • Can send copies to several people at once

Major Disadvantage:

  • You don't know if the receiver actually reads it, though you can find out if they received it. Of course in a phone conversation you don't really know if the person is actually listening either!

  • With no body language or vocal intonations it is difficult to convey the emotional tone you want. Irony and sarcasm are particularly dangerous since your reader may take you seriously.

For more on using email - view Prometheus Project tutorial on email This tutorial is illustrated with an old version of Netscape Mail but the principles are the same for all email.

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