CONTENTS Part One Hardware1 Unit 1 Elementary Knowledge3 Unit 2 Secondary Storage23 Unit 3 Input Device38 Unit 4 Output Device52 Part TwoSoftware65 Unit 5 Application Software67 Unit 6 System Software99 Part ThreeNetwork Application109 Unit 7 The Internet and the Web111 Unit 8 Connectivity118 Unit 9 How to Surf the Web125 Unit 10 Communicating Tools129 Unit 11 Electronic Commerce139 Unit 12 Hidden Trouble of the Internet146