1. Computer Currents
Miguel Rebollo
Introduction to Computer Science
2009-2010

2. Aims
• What is a computer and what it does
• Study current trends in the evolution of modern
computers
• Analyse the fundamental differences between
computers and other machines
• Know the relationship between hardware and
software
• Classify the different kinds of computers
• Understand the social and ethical impact of
information technology on our society
4626. Introd to Computer Science

3. General perspective
• Computers are machines that converts
input data into output information
• Computer’s versatility is built upon its
software
4626. Introd to Computer Science

4. Computers in
perspective
• 1939: first programmable, general-purpose,
digital machine (Konrad Zuse)
• 1943: first electronic, digital computer (Alan
Turing)
• 1944: IBM develops Mark I (based on
Babbage’s analytical machine)
• 1946: ENIAC, Univ. Pennsylvania
• 1951: UNIVAC, first commercial computer
4626. Introd to Computer Science

5. Computer’s evolution
60 years of transistor (1947-2007)
vacuum
transistors
tubes
integrated micro-
circuits processor
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6. Computers today
• Supercomputers
• Servers
• Workstations
• Personal computers
• Portable computers
• Specific purpose computers
4626. Introd to Computer Science

7. Mainframes and
supercomputers
• cost: 1,000,000 €
• used by large organisations
• huge computations tasks
• time sharing: to give short time
periods to each user
• supercomputers: intensive calculus
4626. Introd to Computer Science

8. Servers
• provide services (sw
resources) to several
users among a network
• servers are specifically
designed to this work
4626. Introd to Computer Science

9. Workstations
• high-end desktop
computers
• for users who need
massive computer
power
• scientific applications
4626. Introd to Computer Science

10. Personal computers
• serve a single user at a
time
• powerful enough for
common applications, and
cheaper
• IBM PC is not the only
personal computer (PC)
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11. First IBM PC
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12. Portable computers
• machines that are not tied to
the desktop (less than 3 kg)
• same power as PC
• in the border line: handheld
computers and PDAs
(personal digital assistant)
4626. Introd to Computer Science

13. Specific purpose
• dedicated computers that
performs specific tasks
• their programs cannot be
changed easily, because they’re
stored in their circuits
• embedded computers:
integrated in a lot of devices
(as electronic equipment or
household appliances)
4626. Introd to Computer Science

14. Is this a computer?
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15. And these?
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16. Computer connections
• They appear when terminals are
substituted by PC (60s) →LAN
• Allow to share resources among
computers and to communicate
• Joined forming bigger networks (WAN)
• use of standard telephonic lines
• extended to domestic users in 90s
4626. Introd to Computer Science

17. Internet revolution
• Born for educational and research instit.
• Closely related with WWW development
• Current alternatives to connections:
• network computers (NC)
• household appliances
• games and set-top boxes
• cell phones
4626. Introd to Computer Science

18. Main applications
• Productivity tools
• Graphics and digital photography
• Digital sound and video. Multimedia
• Telecomm. and networks
• Artificial intelligence
• Entertainment
• General problem resolution
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19. Social and ethic
problems
• Threat to personal privacy
• Difficulty to keep data secure
• Difficulty to protect property
• Risk to failures
• Threat to work automation and
deshumanisation
• High dependence of tech
4626. Introd to Computer Science

20. does technology have
to change?

21. ...or is the people who
has to change?