PROBABLY THE MOST important reason for the ripening of the NII (apart from general advances in computer power and memory) is the advent of high-speed digital data transmission. Digital transmission simply means a signal - whether it is a person's voice, a video, or a paragraph of text - is electronically converted into a series of 0's and 1's. In the case of text, for example, each letter of the alphabet has a standardized code made up of eight 0's or 1's. For a picture, an image is broken down into millions of dots, and the darkness of each dot equals another code.

Because the data is now broken down into one of two options, a 0 or a 1, it can be transmitted as an electronic signal, not unlike Morse code. After the signal is transmitted, it is picked up by a machine at the other end and converted back into the original text, image or sound.

As researchers become more familiar with digital transmission, they figure out ways to speed it up. Speed is key when it comes to audiovisual transmission - unlike text, which contains relatively low amounts of information, every second of video and audio are made up of millions of bits of data. Today's standard telephone lines, for example, are designed to handle human voice and fax signals, so if you wanted to transmit a video over the same wire, it would be very, very slow and of terrible quality, all because video is much more complex than sound. One way to speed up the data is to use a different transmission medium. Fiber optic lines, for instance, are much faster than traditional telephone lines. Rewiring a network with faster channels allows for a potential increase in transmission speed.

Because the data is now broken down into one of two options, a 0 or a 1, it can be transmitted as an electronic signal, not unlike Morse code. After the signal is transmitted, it is picked up by a machine at the other and and converted back into the original text, image or sound.

To take advantage of high-speed channels, you must also improve your ability to send the data in the first place. For instance, you can raise efficiency by encoding the data - for example, if you want to send a fax of a report, the fax machine knows that the black dots created by the text occur less than the white which makes up the background. To get a better feel for this, look at this screen. Though the darkness of text stands out, there is still more light than dark. So, to speed up the fax transmission, each instance of white is given a shorter code than each instance of black. The fax also knows when there are long strips of one color, such as the strip of white space between each line of text. Instead of sending the dozens of signals that would make up that white strip, the machine knows another code which represents the whole strip. If a white dot was encoded as 00, a strip of 100 white dots would take up a total of 200 signals, one bit of information for each 0. Digital encoding lets the fax understand that 100 white dots might also be known as 001000, for instance, thus eliminating 194 bits of code and speeding up the transmission.

The potential for high-speed digital data continues to grow. The faster the transmitters and channels get, the more complex the data. With today's technology of fiber optics and computers, multiple audiovisual signals can be sent to another user in real time. It is this leap in science that has allowed for the birth of the information highway.