1. CS 197 Computers in Society Computing Devices

2. Today I see teams. I would like links from people to teams. Any questions on the wiki? We'll go for a short tour of campus IT facilities today. Expect a short quiz at the end of class. I see a team making a news presentation next Thursday:

3. Reading for Tuesday Since we're looking at the "Nuts and Bolts" of computers we'll keep the reading in the Wikipedia.

4. News Presentation Let's talk about the $100 laptop! What is the goal of the OLPC project? What sort of countries are they targeting? Does this project address instructional software? What will they do about lack of power in rural areas? What will they do about lack of internet access?

5. OLPC What were the basic technical challenges of the $100 laptop? Is there any direct evidence that laptops will improve the educational systems? Intel has a $400 laptop – does the price difference between $100 and $400 matter? Intel focuses on teachers instead of students – why?

6. OLPC Can students handle this level of technology? Should they? What sort of hardware do these machines contain? What are they missing? How much power does this machine consume? What is "Constructionist Learning"? Why did the Indian government reject OLPC?

7. Quotes If part of their rationale is that it will revolutionize education in various countries, I don’t think it will happen, and they are naïve and innocent about the reality of formal schooling. If you are going to go have people share the computer, get a broadband connection and have somebody there who can help support the user, geez, get a decent computer where you can actually read the text and you're not sitting there cranking the thing while you're trying to type.

8. Quotes Our view is that systems cannot require professional administration at a local level: we could not deploy quickly on this scale and have sufficient expertise if this were required. Open Source tools are a way to let the Global South develop their own knowledge economies. Microsoft want to restrict the greatest profits in the knowledge economy to already established software corporations like them. By installing their programs on these laptops they hope to create market domination and vendor lock in.

9. Discussion Is investment in education more important than other needs of third world children? Is placing laptops directly into children's hands superior to building schools or libraries? Does this project force western values on children in developing nations? Will this be a form of cultural imperialism? Will the lack of infrastructure (power and internet access) prevent this from being effective in the poorest nations? Will these computers be used by their intended audience or will they be stolen or sold on the black market?

10. Information Storage Storing information is as important as processing it. This all started with written language: Important ideas: Precise relationship between spoken and written languages Ability to make a “perfect copy” of a document A medium (clay, paper, …) is used to preserve information over time

11. Organizing Information Given a large collection of information, how do we find what we need? Alphabetical ordering Dewey Decimal System Indices Long before google, people needed to find things in information collections.

12. Mechanical Access A large information repository is much more useful if it can be accessed quickly via mechanical means. Punch cards predate computers (by a long shot!) and were used to store and process large volumes of information. A key insight was that alphabetic information can be processed as if it is numeric Herman Hollerith patented a system in which needles sensed the presence or absence of holes in a card. This converted information into electric impulses. His machine was used for the 1890 census What company did he start?

13. Storage Media

14. Assessing Storage Technology Read/write or read-only Latency (time it takes to find what you want) (time) Transfer rate (how fast you get the information) (bits / second) Capacity (bits) Cost / bit ($) Error rate (errors / bit) Durability (time)

15. An Aside Measuring the size of information: * A bit = 0/1 = a single piece of information * A byte = 8 bits = 1 alphabet character * Megabyte = 1,000,000 bytes * Gigabyte = 1,000,000,000 bytes * Terabyte = 1,000,000,000,000 bytes

16. Back in the day … When I was starting out in the computer biz, an RK05 was “seriously cool”: Data Transfer Rate: 0.1 MBsecond Latency: 70mS Capacity: 2 megabytes Cost: $8000 (1074) (about 1/5 of a house) Media: $99 / disk

17. Organizing Information The organization of information is no longer mechanical – it’s now done with software. A program that manages larges collections of data and finds things for you is a “database”. (Or maybe “google”).

18. Transmitting Information Moving information from one place to another was simply a matter of moving some sort of media through a transportation network. But many of the issues are still the same: Addressing: how do you tell the system where to send the information? Payment: how are you charged? Packaging: how do you have to encapsulate the information? Speed: how long does it take to deliver? Identity: how can you be sure who send something? Errors: how can you tell if a message was delivered? All of these issues are still here!!!

19. Electronic Message Delivery The telegraph is the ancestor of the Internet Issues: Electronic encoding of messages Relaying messages toward a destination Wireless / wired communication

20. Communication and Computing Nowadays, we can’t imagine computing outside the context of the Internet. Without connections to other computers, our computer is of little use! Yet the integration of communication into the computing world is a very recent thing. We’ll talk a LOT about the Internet later …

21. Technologies How do we move information? Ethernet Wireless (radio) Fiber-optic cable

22. Assessing Communication Latency Communication rate Error rate Distance Privacy

23. Interfacing Getting (electronic) information from or to the real world is another BIG part of computing. The first big breakthrough was a loom controlled by punched cards.

24. Interface Technology The big idea here is converting between electronic representation and human sensing for audio and video objects. Other interface technology includes pointing (mouse), typing (keyboard), and even GPS. We’ll come back here later.

25. The Real Stuff Let's take a short tour of campus IT.

26. Babbage’s Insight Instead of programming a computer mechanically, use the storage to encode the program. That is, instead of building a machine to accomplish just one task, build a general machine that could be programmed to do any task (a “stored program” computer). The same data that a program manipulates can also be the program that controls the machine.

27. Logic Gates A “Logic Gate” is the basic unit of computational processing. Let’s talk about what a logic gate does.

28. Moore’s Law Let’s jump into the Wikipedia for this: http://en.wikipedia.org/wiki/Moore%27s_Law

29. Business vs Defense Two original applications of computation: * Military: specialized calculations; artillery tables, code breaking, radar and sensing systems * Business: simple calculations on large data sets; accounting, billing, census, document software Each application domain led to different sorts of computers

30. Progress: Hardware * Special purpose devices (calculators) * Programmable devices (looms) * Von Neumann machine (general purpose computer) * Faster and faster hardware (design hasn’t changed!) * Bigger and bigger storage devices (finding information gets harder…) * Networking – computers talking to computers

31. The Big Trends Computers are getting faster, smaller, and cheaper Communication is becoming pervasive More and more interactions will take place via computer Your toaster will probably have a computer in it soon Computers are still not simple to use in many application areas Computers raise many big issues in society that have not yet been addressed Everyone needs to be able to use computers and understand how they should or could be used Nobody understands all of the risks as computers become more pervasive