An introduction to computing

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An introduction to computing

• Professor Richard Anderson
• Department of Computer Science and Engineering
• University of Washington
• Seattle, Washington, USA
• July 26, 2007

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My background

• Professor of Computer Science at University of
  Washington in Seattle
• On the faculty since 1986
• Professional Interests
• Educational Technology
• Distance Learning
• Pen Based Computing
• Technology for the Developing World
• Computer Science Education

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Seattle, Washington
Seattle
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Connections with Eritrea

• Personal ties to Eritrean community in Seattle
• University sponsored visit to Asmara in 2001
• Participation in Eritrean community events

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Todays talk

• Introduction to computing
• Demonstrate some key ideas by showing technology
  that we have been working with and developing
• Promote interest in computing
• These technologies are relevant world wide

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Demonstration

• Pen based computing
• Input with a pen, so computers can work with
  handwriting and drawings
• Collaborative application
• Sharing information between computers
• Wireless computing
• Sending data using radio waves

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Draw a picture of yourself

To submit your picture, click on the
button on the tool bar.
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Technology pen based computer

• What is an ink stroke?
• How is the ink stroke represented in the
  computer?
• How is it captured

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Key idea in computing

• Representing data at different levels
• Example the string Hello

H e l l o \0
72 101 108 108 111 0
01001000 01100101 01101100 01101100 01101111 00000000
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How is an ink stroke represented?
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A stroke is a set of pointsRepresent as a
collection of coordinates
11 33
16 21
19 18
23 27
28 44
34 59
39 63
44 61
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The Tablet PC Mobile computing

• Mobile computer
• Use during day to day work
• Stylus based input
• Non-traditional form factor
• A broad range of devices can have computer
  capabilities
• Its not just a desktop machine

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Wireless computing

• How did the ink stroke get from the Tablet PC to
  the display?

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Packet based networkingBreak operations into
small steps

• Data packet
• From Address
• To Address
• Data
• Control information
• Break message into packets
• Send packets in order

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What can go wrong?
A, B, C, D, E, F, G
A, C, D, F, G, E
Packets lost, Packets out of order, Packets
corrupted
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Networking

• Protocols to allow messages to be reconstructed
• Out of order? Use sequence numbers to reorder
  packets.
• Corrupt packet? Use checksum to reconstruct data
  or invalidate packet.
• Dropped packet? Request packets be resent.

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What is computing?

• Working with software
• Developing, maintaining, adapting
• Working with hardware
• Deploying, developing, upgrading, trouble
  shooting
• Working with people
• Understanding how to make computers useful to
  people
• Developing applications for solving real world
  tasks

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Why I am in Eritrea

• Digital StudyHall project
• Facilitated video instruction for education
• Video record lessons
• Show with tutors at remote sites
• Key technologies
• Digital Video, Multimedia Database, DVD
  distribution and replay

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Contact Information

• www.cs.washington.edu/homes/anderson
• For more information, contact
• Richard Anderson
• anderson_at_cs.washington.edu