1. CS 104 – Fall 2011 Exploring Computer Science Lecture 2: August 29, 2011 - Blown to Bits - CS Unplugged

2. General Notes Books  Order App Inventor book (from syllabus)  Download Blown to Bits First Quiz on Wednesday  Ch1 Blown to Bits  CS Unplugged Lecture today Homework 1  Due September 7 ACM Student Meeting  110 AIME  6:30pm Tomorrow Night (Tue)

3. Stories of 0s and 1s http://www.bitsbook.com/excerpts/ “The forces shaping your future are digital, and you need to understand them.”

4. Claude Shannon and Information Theory Wrote “A mathematical theory of communication” that provided the foundational principles for the digital age Father of Information Theory Coined the term “bit” and provided the understanding that the bit represents the fundamental unit of information

5. Moore’s Law Gordon Moore noticed that the number of transistors that can be placed on a chip was doubling about every 18-24 months Currently challenged due to limitations at atomic level Driving need for multicore processors

6. Principles of Bits It’s All Just Bits  An illusion: emails, photos, songs – all just bits! Perfection is Normal  Every copy is perfect; digital copies, law and IP There is Want in the Midst of Plenty  1988: 20MB hard drive more than anyone needed  2011: 2TB hard drive for $100 Processing is Power  Moore’s Law; Metcalfe’s Law; Many similar laws

7. Principles of Bits More of the Same can be a Whole New Thing  Exponential growth; Speed of “disruptive tech”  Kodak, Nokia, Xerox Nothing Goes Away  Data to be mined for the future  Facebook interview challenges Bits Move Faster than Thought  Flat world: Daniel Friedman  Call centers to X-rays – offshored  Fast food order in another state  Governments overturned through social media

8. Technology: Good or Ill - Online child porn predators + Identification of neighborhood offenders on web + Personal privacy in digital communication - Terrorists communicate secretly - Online bullies lead to suicide by those affected + Social media unite old friends and new relationships

9. Bits and Bytes – CS Unplugged Hands-on Discussion  Parity Bits: Error Correction  Binary Numbers  Sorting  Searching