Post on 24-Jan-2015
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Computer CurrentsMiguel Rebollo
Introduction to Computer Science2009-2010
4626. Introd to Computer Science
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
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
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
Computer’s evolution
vacuumtubes
integratedcircuits
transistors
micro-processor
60 years of transistor (1947-2007)
4626. Introd to Computer Science
Computers today
• Supercomputers
• Servers
• Workstations
• Personal computers
• Portable computers
• Specific purpose computers
4626. Introd to Computer Science
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
Servers
• provide services (sw resources) to several users among a network
• servers are specifically designed to this work
4626. Introd to Computer Science
Workstations
• high-end desktop computers
• for users who need massive computer power
• scientific applications
4626. Introd to Computer Science
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)
4626. Introd to Computer Science
First IBM PC
4626. Introd to Computer Science
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
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
Is this a computer?
4626. Introd to Computer Science
And these?
4626. Introd to Computer Science
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
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
Main applications
• Productivity tools
• Graphics and digital photography
• Digital sound and video. Multimedia
• Telecomm. and networks
• Artificial intelligence
• Entertainment
• General problem resolution
4626. Introd to Computer Science
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
does technology have to change?
...or is the people who has to change?