A Short History of Computers

Geoffrey M. Rockwell

x 24072

Togo Salmon 309A

grockwel@mcmaster.caURL: http://www.humanities.mcmaster.ca/~hccrs/ihchome.htm

McMaster University

Administration

Homework 3 is up. Complete by next Wednesday.

Review - Types of Storage

Storage

Permanent Temporary

ROM

Removable Fixed

Hard Drive

Floppy

CD-ROM

RAM

Magneto-Optical

Storage typically measured in K (Kilobytes),

MB (Megabytes) orGB (Gigabytes)

Storage (bits and bytes)

• Computer is digital.• Information has to be

digitized. (binary digits)• Bits and Bytes

• Bit - 0 or 1/On or Off/• Byte - Eight Bits 00110011• K (Kilobyte) 1024 bytes• MB (Megabyte) about 1000 K• GB (Gigabyte) about 1000

MB

Letter ASCII A 01000001 B 01000010

Number Binary 0 0 1 1 2 10 3 11 4 100 5 101

Kbps = Kilobits per second

Review - From letters to bytes

“A” 1 Byte01000001

off.on.off.o

ff.off.o

ff.off.o

n

Floppy DiskCD-ROM

Laser

(8 Bits)

Brief History of Computing

Prehistory - Babbage and Lovelace The first computer? - ENIAC The first home computer? - Altair Accessible computing - Apple Micros go business - IBM PC

Babbage and Lovelace

Charles Babbage (1791-1871) Difference Engine 1833 1835 Analytical Engine

Programmable (Cards) Mechanical

Ada Lovelace“It weaves algebraic patterns just as the Jacquard loom weaves flowers and leaves” (Ada Lovelace)

Gibson - “The Difference Engine”

ENIAC

Mauchly and Eckert - 1943 proposal to Army

ENIAC (Electronic Numerical Integrator and Computer) working in 1945 (after the war)

von Neumann - EDVAC Transistor invented in 1947 ICs - Integrated Circuits Microprocessor (Intel 4004) 1971 Printer

ENIAC Pictures

Programming with switches

Engineers

The initiating and cycling units of ENIAC

Altair - the Microcomputer

MITS - Altair Uses the Intel 8080 Cover of Popular Electronics

Jan. 1975 MITS hires Allen (and Gates)

Apple

Steve Wozniak (the Woz) Steven Jobs Homebrew Computer Club Apple I - MOS 6502 chip 1976 Mike Markkula bought in

Apple Founded 1977 the Apple II 1984 the Macintosh

IBM PC

Built on the Intel 8088 Operating System from Microsoft (and others)

Put together with existing components Open to cards and software Released in 1981

An IBM Clone

Key Innovations

Calculating device General Purpose Device - Programmability Digital Device Electrical Device Integrated Circuits - Transistors Interface from Commands to GUI Multiuser/Shared Computer to Personal

Computer

History of the Net

Sputnik and The Space Race ARPA and the ARPANET E-Mail and the subversion of the Net Who has access, really?

Birth of the Internet

Sputnik - 1957 Advanced Research

Project Agency - 1958 RFP for Interface

Message Processors (IMPs) - 1968

UCLA and SRI connected in 1969

IMP

Evolution of the Internet

Ethernet - Bob Metcalfe - 1973 ARPANET splits off MILNET - 1983

113 nodes, 45 go to ARPANET TCP/IP - 1978, ARPANET switches in

1983 ARPANET replaced by NSF backbone -

1985

History of E-mail and Web

MAILBOX on MIT time-sharing system, early 1960s

Ray Tomlinson - MAIL - @ symbol - 1972 3/4 of ARPANET traffic is e-mail in 1973 1990 - World Wide Web

Tim Berners-Lee, CERN 1995 - Netscape. Netscape Corp is traded

on the stock market.

Internet Census

1997

1991

Current State of the Net

Who has access? Who doesn’t?

End