Book excerpt: Preface; Introduction; The internet; Microcomputer fundamentals; System architecture and construction; The PC expansion buses; Semiconductor memory; Printers and the printer interface; The serial communication ports; Replaceable disk drives; Hard disk drives; Displays; Viruses; Troubleshooting Windows error messages; Troubleshooting Windows registry; Appendices; IndexIntroduction -- The Internet -- Microcomputer fundamentals -- System architecture and construction -- The PC expansion buses -- Semiconductor memory -- Printers and the printer interface -- The serial communication ports -- Replaceable disk drives -- Hard disk drives -- Displays -- Viruses -- Troubleshooting Windows error messages -- Troubleshooting Windows registry.