Accessing the World Wide Web

You need to be aware that not all Internet connections are created equal. If you are in a school computer lab or a public library the institution may have multiple computers connected to the Internet via one dedicated high speed route. These connections may be referred to as a T-1 line, a partial T-1, or a 56K connection. From one of these high speed Internet connections, when you open a graphic intensive WWW home page, you'll be looking at the images within seconds.

However, if you are doing these lessons from home or from a location without a dedicated connection you are probably using a modem and dialing into a service for Internet access. Most likely you have either a SLIP (Serial Line Interface Protocol), or PPP (Point to Point Protocol) account. Using a SLIP or PPP connection, even with a 28.8kps or higher speed modem, you might sit for 2 minutes waiting for that same web page to download before you can see it. WWW servers designed to accommodate direct as well as dial-up users must be sure to keep all image files small enough to allow for realistic wait times while downloading.

Most browsers have the option to "Turn Images Off" to allow faster response time for text-only browsing. For Netscape users: select the Edit/Preferences/Advanced menu and deselect "Automatically Load Images."

Lynx - A Text-Only Web Browser
Finally, there is the possibility you are accessing WWW via dial-up without a SLIP connection. In this case you are probably using a text-only browser, usually a UNIX browser named Lynx. You'll see all the text in simple ascii format but you won't be able to see the graphics or multimedia sections of a web page while online. Instead, you will see [IMAGE] (or the name of the image in square brackets) wherever an image is available within a page. If the [IMAGE] is highlighted you can save it to your file area by pressing return and choosing a filename when prompted. Once saved to your UNIX account you can download the image and later view it with a separate image viewing software program. (More on how to do this in Unit Three of this course.)

While images are often entertaining, the most functional information is usually in text form.

Multimedia
As you begin surfing the net you will come across movie files, sound clips, or animations. It is important to note that many of these multimedia components can not be run without additional software called "Helper Applications". For example' Netscape Communicator Version 4.0 has an integrated Quicktime viewer for watching Quicktime videoclip files. Much of the other software needed for the other functions is available from the Plug-Ins section of Netscape's web site (http://www.netscape.com). One of the more interesting plug-ins that is also included with Netscape is the RealPlayer module which allows you to hear sound files and watch videoclips as they download, saving time on slow speed connections and allowing access to "real-time" feeds such as broadcasts from radio or television stations. You will need the necessary hardware such as speakers to hear audio segments.

Activity
1. In your web browser software turn off images and view several pages, such as the main Reach for the Sky page, that you have viewed before to compare what they look like without graphics.