CS 197Computers in Society

Computing Devices

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:

Reading for Tuesday

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

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?

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?

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?

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.

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.

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?

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

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.

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 censusWhat company did he start?

Storage Media

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)

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

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: 70mSCapacity: 2 megabytesCost: $8000 (1074) (about 1/5 of a house)Media: $99 / disk

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”).

Transmitting InformationMoving 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!!!

Electronic Message Delivery

The telegraph is the ancestorof the Internet

Issues:• Electronic encoding of

messages• Relaying messages toward a

destination• Wireless / wired communication

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 …

Technologies

How do we move information?• Ethernet• Wireless (radio)• Fiber-optic cable

Assessing Communication

• Latency• Communication rate• Error rate• Distance• Privacy

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.

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.

The Real Stuff

Let's take a short tour of campus IT.

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.

Logic Gates

A “Logic Gate” is the basic unit of computational processing.

Let’s talk about what a logic gate does.

Moore’s Law

Let’s jump into the Wikipedia for this:

http://en.wikipedia.org/wiki/Moore%27s_Law

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 softwareEach application domain led to different sorts of computers

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

The Big TrendsComputers are getting faster, smaller, and cheaperCommunication is becoming pervasiveMore and more interactions will take place via

computerYour toaster will probably have a computer in it soonComputers are still not simple to use in many

application areasComputers raise many big issues in society that have

not yet been addressedEveryone needs to be able to use computers and

understand how they should or could be usedNobody understands all of the risks as computers

become more pervasive