Continuing with Chapter 1

Please read all of chapter 1.

Parts of a computer

• CPU - Central Processing Unit
  • ALU - Arithmetic Logic Unit
  • Registers
  • Cache
  • Control Unit
  • Clock
• Memory
  • Measured in Megabytes
  • Where a program and its data is stored when executing
  • Bigger is better
• Main Storage (Hard Drive)
• Secondary Storage
  • Floppy
  • Tape
  • CD/DVD
  • Zip
  • ...
• I/O Devices, peripheral devices
  • Keyboard, Mouse
  • monitor
  • printer, scanner
  • modem, lan card ...

Classes of Computers

• Mainframe
• Minicomputer
• Workstation
• Microcomputer
• Supercomputer
• Cluster
• The first four terms are semi-meaningless

Software

• Operating System
  • Unix, linux, solaris, hpux, aix, ...
  • Windows
  • VMS
  • VM
• Utility Software
  • ls
  • cs
• Application Software
  • g++
  • joe
  • Netscape

Ethics

• Knowing how to do something doesn't mean it is right to do it.
  • Breaking into an account.
  • Building a bomb.
  • Writing or using a computer virus.
  • Writing or using a security breaking program.
  • Academic curiosity - ASK FIRST
• Stealing is stealing, knowledge, information or product
  • Moral dilemma, steal to feed your family
  • No question, steal to play a game.
  • Stealing information
  • Stealing computer time.
• Quality of work
  • Who is responsible when a bridge collapses?
  • How about when software doesn't work right?

Problem Solving Techniques

• This is at best an overview, we will use these approaches constantly in class.
• Ask Questions
  • Understand the problem
  • Understand the input
  • Understand the output
  • Understand what can go wrong, and what to do.
  • Understand when you are done.
• Look for things that are familiar
  • Is this the same as something else I did before?
  • If you can avoid rewriting code, do so.
  • If you can use a library or utility do so.
• Solve by Analogy
  • Is this like something else I did before?
  • as above, but this time not programming.
  • Look for solutions from life, don't limit yourself to just programming and computing.
  • Book's example, library cataloging is similar to an inventory control system
• Means-Ends analysis
  • Given a starting point and an ending point, how do I bridge the gap between them?
  • List all of your choices then eliminate bad ones or pick good ones.
  • This can be an iterative process.
  • Example: How do I Make a bunch of money

    Make a bunch of money	Lottery Get A Job Inherit
    Make a bunch of money Get a job	Start at the bottom, work my way up Start my own company Get a Degree, start further up.
    Make a bunch of money Get a job Intermediate GoalGet a degree.	Ivy League College State School Bob's Business College

• Divide and Conquer
  • How can I break this problem into smaller parts?
  • Getting a degree is tough, passing a class is tough, passing a test is manageable.
• Building Block Approach
  • Can I build a little piece of the solution?
  • Don't look at it as a degree, look at it as a series of tests.
  • Different from divide and conquer, but similar.
• Merging Solutions
  • If I have some pieces that solve part of the problem, can I put them together for a final solution?
• Overcoming a Mental Block
  • Write the program down so you understand it.
  • Write something down.
  • Write an experimental program, build on that.
  • Strive for understanding.