ISP 121 Personal Computers

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ISP 121Personal Computers
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A Little History
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Personal Computers
When were the worlds first minicomputer and
first mass-produced minicomputer created?
A. 1945
C. 1965
B. 1957
D. 1970
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About the First Minicomputer

• Created by Digital Equipment Corp. (DEC) which
  was founded by Ken Olsen and Harlan Anderson
• It was named the PDP-8
• It cost 18,000
• It was marketed to businesses.

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Personal Computers
What company was founded in 1976 and
revolutionized personal computing ?
Apple Computers
The Apple II microcomputer, introduced in 1977
and was a hit with home users. Apple II
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About the Founders of Apple Computers

• Founded by Steve Jobs and Steve Wozniak.
• Steve Jobs sold his Volkswagon minibus and Steve
  Wozniak sold his scientific calculator for a
  total of 1,300 to raise money to start the
  business.

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The Rival
In 1980 IBM decided to market a low-cost
single-user personal computer in response to
Apple Computer's success in the burgeoning
market.
On 12 August 1981, the first IBM PC went on sale.
There were three operating systems (OS) available
for it but the most popular and least expensive
was DOS. IBM licensed DOS from Microsoft and
named it PC-DOS (also known as MS-DOX for non-IBM
platforms).
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Operating Systems
It was the most widely used member of the DOS
family of operating systems and was the dominant
operating system for the PC compatible platform
during the 1980s.
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Interfaces
The Macintosh (MAC), from Apple Computers was
named after the McIntosh apple. The original
Macintosh was released on January 24, 1984. It
was the first commercially successful personal
computer to use a graphical user interface (GUI)
and mouse instead of the then-standard command
line interface.
Microsoft first introduced Windows in November
1985 as an add-on to MS-DOS in response to the
growing trend of graphical user interfaces (GUI)
popularized by the Macintosh.
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Early Video Games
The original Atari was founded in 1972 and it was
a pioneer in arcade games, home video game
consoles, and home computers.
The original PONG arcade unit was released by
Atari on November 29, 1972. It was certainly the
first video game to win widespread popularity, in
both its arcade and home console versions.
The Atari 400 was designed primarily as a
computer for children. It has an "advanced
child-proof design featuring pressure-sensitive,
wipe-clean keyboard and a single cartridge port
under the front cover.
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and Now
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How do Computers Store Numbers?
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How do Humans Count?

• The Babylonians used a base-60 numbers system.
  How is it used today?
• The Hindu-Arabic numeral system is a base-10
  system which we commonly represent by using 0,1,
  29. Why does this system make sense?

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How do Computers Count?

• Computers are logical electronic devices.
• The data is just a combination of two states
  on or off.
• These states are called binary digits or bits and
  have either the value of 0 or 1.
• This is considered a base-2 or binary number
  system.

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Binary Number System

• Maximum number of different values that can be
  represented by n bits is 2n.
• One byte 8 bits
• Computers start counting at zero
• Binary numbers can be written with a subscript 2
• Uses a place system