计算机文化(全英)_Chapter01.ppt

* * * * Figure 1-42 * * * Figure 1-45 * Figure 1-46 * Figures 1-47 and 1-48 * * * Figure 1-12 * Figure 1-13 * * * * Figure 1-14 * Figure 1-15 * Figure 1-16 * * Figures 1-17 – 1-18 * * * Figures 1-19, 1-20, 1-21 * Figure 1-22 * * * Figure 1-23 * Figure 1-24 * Figures 1-25 – 1-26 * Figure 1-29 * Figures 1-30 and 1-31 * Figure 1-32 * * * * Figures 1-34 – 1-35 * * * Figure 1-36 * * Figures 1-37 – 1-38 * Figure 1-39 Programs and Instruction Sets Chapter 1: Computers and Digital Basics * Chapter 1: Computers and Digital Basics * Processor Logic The ALU (arithmetic logic unit) is the part of the microprocessor that performs arithmetic operations The ALU uses registers to hold data that is being processed The microprocessor’s control unit fetches each instruction, just as you get each ingredient out of a cupboard or the refrigerator The term instruction cycle refers to the process in which a computer executes a single instruction Chapter 1: Computers and Digital Basics * Processor Logic Chapter 1: Computers and Digital Basics * Processor Logic Chapter 1: Computers and Digital Basics * Password Security Authentication Protocols Password Hacks Secure Passwords Question 012500 Security experts stress that the use of “strong” passwords can prevent identity theft and help to keep your computer files secure. Which of the following passwords is likely to be the most secure? A. 12345 because it is all numbers. B. Hippocampus, because it is a long and unusual word. C. Il2baomw, because it combines numbers with a nonsense word. D. Football88, because it combines a word and numbers. * * Chapter 1: Computers and Digital Basics Chapter 1: Computers and Digital Basics * Authentication Protocols Security experts use the term authentication protocol to refer to any method that confirms a person’s identity using something the person knows, something the person possesses, or something the person is A person can also be identified by biometrics, such as a fingerprint, facial features (pho