The Internet，unlike other media such as TV or radio，is inherently(本身固有地) a“two—way”medium．A company user can communicate to the rest of the world with ease．It has created a sense of“global community”that’s found almost nowhere else．People around the world post web sites，exchange e—mail，and participate in on-line chats．Going on—line means not just surfing the Web and reading e—mail．It means getting involved in the whole Net community．