When the Internet was first opened to the general public, it was a text-only medium. One computer could send a message to others using a system not unlike the ones used by the telegraph company or news wire service. Signals went from the computer to a box called a modem, and then as tones over a telephone line to another computer. The signals again passed through a modem and were translated back into letters and numbers on the receiver's computer screen. The system was originally developed as a means of secure communication for science facilities, the armed forces, and university researchers. Eventually, it was opened to the general public.
Modem stands for modulate/demodulate. The modem translates ASCII text into audible signals that are sent back and forth on a normal telephone line.
Words are good, but some things require pictures. ASCII graphics, like the example in Figure 11.1, were the first attempt at graphics on the Internet. Obviously, they weren't very successful.
Figure 11.1. ASCII graphics were cute, but not very successful as art.
CompuServe developed the first usable graphics format, called GIF, which let users display either line art or photos with a limited palette by downloading them to the screen, one picture at a time. The GIF format was originally the exclusive property of CompuServe, which was also one of the earliest web service providers. GIF pictures were first shared among CompuServe users who downloaded them from text files. Before long the web was opened to businesses and individuals who signed up for their own web addresses, called domains, and used a service provider to host these websites.
The most popular language used to publish documents on the web is still HTML (Hypertext Markup Language). HTML isn't really a computer programming language, so relax. It is, as its name suggests, a markup language. A series of relatively simple tags enables you to specify how text appears in the browser and arranges for images and links to other sites. HTML isn't difficult to learn, but you really don't need to. (If you decide to get into it, look for Sams Teach Yourself HTML and XHTML in 24 Hours. It's an excellent reference.)
There are programs, including web page design programs, desktop publishing programs, web browsers, and word processors you might already own, that can translate your pages into HTML with just a couple of mouse clicks. All you do is lay out the page the way you'd like it to look with your Photoshop pictures pasted in. Most of the programs described convert your images to web formats automatically. If the one you're using doesn't offer that service, you have to do the conversion first. Because web pages can be viewed on all kinds of computers, the graphics have to be in a format that's common to as many as possible and compatible with the HTML requirements. A web browser will not, for example, display a PSD or TIFF file. Instead, it requires that graphics files be compressed or optimized so that they are as small as possible. This limits your web graphic options to the GIFs previously mentioned or to JPEG (Joint Photographic Experts Group) or PNG (Portable Network Graphics) formats. ImageReady saves in all three of these formats.