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1) Administrivia
 - me
 - info sheet
 - check site and email often
 - talk to me about conflicts, disabilities, or meaning of life

2) Dire warnings
 - like a language class in time commitment and nature, b/c it needs to be
 - probably something to do for every class period
 - do not fall behind in this class
 - come to class, or don't bother taking it
 - do not expect to sit silently (switch to big lecture)
 - not for ppl with extensive programming or some OOP (talk to me)

3) Homework
 - explore sites
 - register for codelab & do the 2 exercises outside of any chapter
 - read chapter 0

4) Intro to computer science (for your technical knowledge only)

**Programs?   - taking initial data, doing calculations, showing results
  Programming - learning a language with a new kind of grammar and giving the
			computer instructions in it

**How the computer works
 - CPU, main memory, hard disks, I/O devices
 - OS brings program from hard disk to main memory
 - CPU executes each instruction of the program
 - it uses main memory to store intermediate calculations
 - it uses I/O devices to get input or display output (GUI / text window)
 - to the uninitiated, user interface seems to BE the program

**Binary numbers
 - data?   (numbers, letters- represented by number codes anyway)
 - but numbers in computer aren't in base 10, they're in base 2
 - the only digits are 0 and 1, instead of 0-9: binary digits -> "bits"
 - but just as you can make any number using 0-9, you can using 0-1
 - represent numbers 0 - 10 in binary (you can do math, too)
 - with two bits, how many different numbers?  (4)    with three?   (8)
 - n bits gives you 2^n numbers. how many to represent alphabet?   (5)

 - memory = switches called transistors: each switch is one bit; on/off
 - why not base 10?   (10-way switches are hard to get right! would crash.)
 - luckily you program with normal base 10 numbers; computer can translate
 - but this is how it's working under the hood

**Main Memory
 - like a table with 8 bits per row: a byte, each with its own address
 - mine has 512 MB, which means 512 X 2^20 rows (~512 mill)
 - hard drives have around 30 GB, which is ~30 bill rows
 - main is smaller and temporary, hard drive is huge and permanent
 - I'll draw sections of memory all over in diagrams later

 - when running program, space for storing it - it's just text (numbers)
 - some scratch space for what it's working on right now - stack
 - some for longer lasting data, called objects - heap
 - and some for program-long data, called static or constant
 - these might hold whole numbers, floating point numbers, words, or even
 	addresses of other memory locations (drawn as arrows)
 - CPU does magic: reads binary #s that contain instructions,
	changes binary #s that are data, sends instructions to I/O

**How programming developed
 - first people wrote machine language; all in 0's and 1's - grunts
 - then they made assembly language, with words like "add" and "store" that
	translate directly into 0's and 1's - see spot run 
 - then they made high-level languages, with more words and power, which don't
 	translate directly - better for humans (Java- newish high-level)
 - a compiler program is needed to translate it into machine language
 - CodeWarrior is our compiler (I'll randomly interchange with CodeLab)
 - you'll type program in a text "source file", compile, run
 - slight difference with Java: compiler translates into "bytecode", and an
 	"interpreter" executes (runs the same even on different machines)

 - you can get errors both when compiling and when running
 - compile-time: a mistake with the language - said something ungrammatical
 - run-time: mistake with instructions - said something silly
 - also: mistake with logic, correct but undesired - slip of the tongue

5) Simple demo program

6) Why a language? Why not make a compiler to translate English?
 - huge vocabulary, many redundant words, complicated grammar
 - ambiguity
 - computer is a stupid, stupid machine. it can only do exactly what you tell
 	it to. so everything you say must have exactly one clear meaning.
 - so you have to learn this language: mostly English & math, but stricter
 - there are lots and lots of languages, many mutually unintelligible, but
 	Java is new and popular and somewhat user-friendly
 - need grammar, and lots of problem solving to write correct instructions

7) Do some puzzles to sharpen up those abilities

	1) Boy crossing river
	- Take rabbit over
	- Take lettuce over and take rabbit back
	- Take fox over
	- Take rabbit over again

	2) Finding the celebrity
	- Must eliminate one person from consideration with each question
	- By asking "X, do you know Y?", you can eliminate either X or Y

	3) One light stack of coins in ten
	- Number the stacks and take 1 from stack 1, 2 from stack 2, etc
	- Weigh the samples all together; if all were good it'd weigh 55 grams
	- The number of missing grams is equal to the counterfeit stack number

	4) Natives and visitors
	- If Joe were telling the truth, then he would be a visitor, so he 
	wouldn't be able to tell the truth. So Joe must be lying, and we know 
	two things: at least one of them is a native, and Joe is a visitor.
	- If Frank were a visitor, then Bill would have to be a native; but 
	that would make Frank's statement true, and he couldn't tell the truth.
	So Frank must be a native, and therefore Bill is a visitor.

	5) Hunter and bear
	- North pole; white

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