Television-----the most pervasive and persuasive of modern technologies, marked by rapid change and growth-is moving into a new era, an era of extraordinary sophistication and versatility, which promises to reshape our lives and our world. It is an electronic revolution of sorts, made possible by the marriage of television and computer technologies.
The word television, derived from its Greek and Latin roots, can literally be interpreted as sight from a distance. Very simply put, it works in this way: through a sophisticated system of electronics, television provides the capability of converting an image into electronic impulses, which can be sent through a wire or cable. These impulses, when fed into a receiver , can then be electronically reconstituted into that same image.
Television is more than just an electronic system, however. It is a means of expression, as well as a vehicle for communication, and as such becomes a powerful tool for reaching other human beings.
The field of television can be divided into two categories determined by its means of transmission. First, there is broadcast television, which reaches the masses through broad-based airwave transmission of television signals. Second, there is nonbroadcast television, which provides for the needs of individuals or specific interest groups through controlled transmission techniques.
Traditionally, television has been a medium of the masses. We are most familiar with broadcast television because it has been with us for about thirty-seven years in a form similar to what exists today. During those years, it has been controlled, for the most part, by the broadcast networks, ABC, NBC, and CBS, who have been the major purveyors of news, information, and entertainment. These giants of broadcasting have actually shaped not only television but our perception of it as well. We have come to look upon the picture tube as a source of entertainment, placing our role in this dynamic medium as the passive viewer.
2015春冀教版英语四下《Lesson 18 Maddy the Monster》ppt课件1
2015春冀教版英语四下《Lesson 20 My Favourite Clothes》ppt课件2
2015春冀教版英语四下《Lesson 16 How Do you walk to school》ppt课件3
2015春冀教版英语四下《Lesson 10 Rain and Sun》ppt课件4
冀教版(三起)四下《Lesson 4 Where Is It》ppt课件
2015春冀教版英语四下《Lesson 16 How Do you walk to school》ppt课件4
2015春冀教版英语四下《Lesson 2 Is this your pencil》ppt课件3
2015春冀教版英语四下《Lesson 15 Where Do You Live》ppt课件1
2015春冀教版英语四下《Lesson 2 Is this your pencil》ppt课件1
冀教版(三起)四下《Lesson 27 My Favourite Food》ppt课件
冀教版(三起)四下《Lesson 31 The Diffos》ppt课件
2015春冀教版英语四下《Lesson 17 What do You like to do》ppt课件2
冀教版(三起)四下《Lesson 7 Little Zeke》ppt课件
2015春冀教版英语四下《Lesson 13 How Old Are You》ppt课件4
2015春冀教版英语四下《Lesson 17 What do You like to do》ppt课件4
2015春冀教版英语四下《Lesson 14 Are You Short or Tall》ppt课件2
冀教版(三起)四下《Lesson 3 Is This Your Pencil》ppt课件1
2015春冀教版英语四下《Lesson 10 Rain and Sun》ppt课件2
2015春冀教版英语四下《Lesson 10 Rain and Sun》ppt课件3
2015春冀教版英语四下《Lesson 14 Are You Short or Tall》ppt课件1
2015春冀教版英语四下《Lesson 16 How Do you walk to school》ppt课件2
冀教版(三起)四下《Lesson 28 My Favourite Subject》ppt课件
2015春冀教版英语四下《Lesson 11 How’s the Weather Today》ppt课件1
2015春冀教版英语四下《Lesson 19 My Favourite Colours》ppt课件1
冀教版(三起)四下《Lesson 5 How Many Books Do I have》ppt课件
2015春冀教版英语四下《Lesson 14 Are You Short or Tall》ppt课件3
冀教版(三起)四下《Unit 2 Days and Months》ppt复习课件
2015春冀教版英语四下《Lesson 17 What do You like to do》ppt课件1
冀教版(三起)四下《Lesson 5 How Many Books Do I have》ppt课件3
冀教版(三起)四下《Lesson 5 How Many Books Do I have》ppt课件1
| 不限 |
| 英语教案 |
| 英语课件 |
| 英语试题 |
| 不限 |
| 不限 |
| 上册 |
| 下册 |
| 不限 |