Televiion-----the mot pervaive and peruaive of modern technologie, marked by rapid change and growth-i moving into a new era, an era of extraordinary ophitication and veratility, which promie to rehape our live and our world. It i an electronic revolution of ort, made poible by the marriage of televiion and computer technologie.
The word televiion, derived from it Greek and Latin root, can literally be interpreted a ight from a ditance. Very imply put, it work in thi way: through a ophiticated ytem of electronic, televiion provide the capability of converting an image into electronic impule, which can be ent through a wire or cable. Thee impule, when fed into a receiver , can then be electronically recontituted into that ame image.
Televiion i more than jut an electronic ytem, however. It i a mean of expreion, a well a a vehicle for communication, and a uch become a powerful tool for reaching other human being.
The field of televiion can be divided into two categorie determined by it mean of tranmiion. Firt, there i broadcat televiion, which reache the mae through broad-baed airwave tranmiion of televiion ignal. Second, there i nonbroadcat televiion, which provide for the need of individual or pecific interet group through controlled tranmiion technique.
Traditionally, televiion ha been a medium of the mae. We are mot familiar with broadcat televiion becaue it ha been with u for about thirty-even year in a form imilar to what exit today. During thoe year, it ha been controlled, for the mot part, by the broadcat network, ABC, NBC, and CBS, who have been the major purveyor of new, information, and entertainment. Thee giant of broadcating have actually haped not only televiion but our perception of it a well. We have come to look upon the picture tube a a ource of entertainment, placing our role in thi dynamic medium a the paive viewer.[由Www.haozuowen.com整理]