history section 3 Flashcards
incomplete ends right before XEROX Parc
batch-orientated computing
programmer would design their program (as a series of punched cards) and send it to a computer operator, who would run the program at a scheduled time. The output (printed sheets of paper) would be returned to the programmer.
interactive computer
takes inputs as it runs
what was the earliest interactive computer?
Project Whirlwind
why was project whirlwind commissioned?
the U.S air force needed a flight simulator that would prepare trainees for flying any plane. Jay Forrester at MIT was put in charge of this.
why was Forrester’s original plan for WhirlWind not fast enough?
it used an analog design
how did Forrester make Whirlwind faster?
he took after the ENIAC project and used digital circuits
why was funding for Whirlwind almost cut?
Whirlwind turned into a project to just create the faster computer and world war 2 ended, so there wasn’t the same demand for the original flight simulator.
why was the funding for Whirlwind saved?
the U.S learned that their cold war rival, the Soviet Union was in possession of nuclear weapons, so they wanted Whirlwind to continue with a focus on air defense
what were the main parts Whirlwind used?
cathode-ray tube display screen, printer, and core memory
what did IBM rename Whirlwind upon receiving it from MIT?
AN/FSQ-7 computer
what were the AN/FSQ-7 computers used for?
they were the basis of the Air Force’s SAGE (Semi-Automated Ground Environment) air defense system
what did IBM use their experience with SAGE for?
an interactive reservations system for American Airlines to replace manual airline reservations. This system, SABRE (Semi-automatic Business Research Environment) was fully operational by 1964.
timesharing
pioneered by John McCarthy at MIT. connected many keyboard terminals to a central computer, so many people could use the computer at once.
CTSS
a timesharing system that was developed by Fernando Corbato and his team at MIT. ran on a 28-megabyte disk drive. each user was allocated part of the disk where they could store their data.
teletype keyboard
used in the CTSS system. A keyboard and printer in one, the user types and the results are instantly printed on paper without a display screen.
what did the teletype keyboard pioneer?
the “Escape” and “control” keys
BASIC timesharing system
(Beginners’s All-Purpose SYmbolic Instruction Code) created by John Kemeny and Thomas E. Kurtz, two Dartmouth professors. they wanted to make a programming language for beginners.
how was BASIC ran?
it translated lines of the program into machine code one line at a time, rather than translating the entire program at once. this gave users instant feedback on the correctness of their program.
what company readily adopted BASIC?
General Electric. They saw it as an opportunity to get ahead of IBM - because IBM did not adapt the program.
What was Microsoft’s first product in 1975?
a scaled down version of BASIC for personal computers
Multics
the successor to CTSS. General Electric, MIT, and AT&T Bell Labs worked together to design this system.
what were the creator’s goals for Multics?
to design it so that it could support 300 users at once. unfortunately it took a lot longer than expected and was ultimately disappointing (only supported 25 users)
“Second-system effect”
term coined by Fred Brooks, where he explains that the general tendency is to over-design the second system using all the disregarded ideas from the first. (true for Multics)
why did so many Timesharing startups in the 1960s fail?
getting multi-user software to work reliably was hard, and decreasing hardware costs meant more people just bought their own computer rather than paying for timesharing.
Digital Equipment Corporation (DEC)
computer company responsible for reduction in computer costs. Founded by Kenneth Olsen, who had previously designed the core memory for project whirlwind.
PDP-1 (programmed data processor)
DEC’s first computer. it was equally powerful to other computers, but far cheaper.
PDP-8
the first “minicomputer” (refrigerator sized), this was completely unheard of and the model was also very cheap.
what niche did PDP-1 fill?
low-cost computers for scientists, engineers, and other tech savvy people because DEC assumed their users could write their own software and didn’t provide them with any.
OEM (original equipment manufacturer) industry
due to its small size and affordability, companies would buy PDP-8 and modify it for specialized applications which they would resell.
PDP-11
the quintessential minicomputer, and one of the most impactful machines in computing
how did PDP-11 use time-sharing?
allowed organizations to run time-sharing in house, rather than having them subscribe to a remote time-sharing service
how did PDP-11 affect BASIC?
PDP-11’s operating system, RSTS-11, expanded the languages reach
what programming language was originally written on PDP-11?
C programming language at AT&T Bell Labs
which influential operating system was created for the PDP-11?
The Unix - the basis for iOS operating systems
which microprocessor was patterned after PDP-11?
the Motorola 6800 microprocessor used in Apple’s early Macintosh computers
what computer did two Bell Labs employees, Ken Thompson and Dennis Ritchie, use to make their new operating system?
PDP-7
what operating system did Ken Thompson and Dennis Ritchie make?
Unix
what computer did Thompson and Ritchie convince Bell Labs to purchase?
PDP-11 to continue Unix development
C programming language
Unix is written in this language. It has a few high-level capabilities but still grants programmers low-level access to the computers memory.
why was AT&T (Bell Lab’s owner) hesitant to commercialize unix?
it was a gov regulated monopoly and was not supposed to enter any venture not related to its core business
where was UNIX sold to?
universities. At Berkeley a popular modified version (“BSD Unix”) was developed by students
J.C.R LIcklider
a director within Advanced Research Projects Agency (ARPA). he wanted to network computers together to make them more available for researchers
what made the ARPANET different from other timesharing systems?
other time-sharing systems were designed around one computer. but the computers on ARPANET came from a variety of vendors.
how could communication on ARPANET flourish amid so many different host computers?
an IMP, sometimes called a node, served as an intermediary between the host computer and the rest of the network.
how were the IMP nodes connected?
major nodes were connected, and those major nodes were connected to smaller nodes nearby
“store and forward”
a term that describes the old way of passing on telegrams from office to office. the telegrams were printed and stored until operators were ready to forward it.
“packet switching”
between the IMP nodes, messages were broken into small chunks called packets. When a packet reached another node, the node would check the packet’s address and send it on as needed.
why was packet switching vital?
they made it so no one single message would monopolize the networks bandwidth
TCP/IP
protocol developed by Vint Cert and Bob Kahn that made it so each host computer could connect to the network without an IMP.
Email on ARPANET
introduced in 1971 and quickly became the network’s biggest source of traffic
what operating system did ARPANET use?
Unix
Usenet
a network created by universities who were not connected to ARPANET. Had an email service and also “newsgroups” which was basically reddit
CS net
gave computer sci departments at universities without ARPANET the ability to send emails
BITNET
network started by the City University of New York that allowed users to access the university’s IBM mainframes
NSFNET
network created in 1986 by the Nation Science Foundation. Originally was only available for government and universities, but gradually opened to public which allowed internet to flourish in the 1990s.
The Minitel Network
A french network that was well funded because france was putting big investments into national telecommunications
Minitel terminals
eliminated the cost of printing paper phone books. users could look up phone numbers, check the weather, order train tickets, etc.
ALOHAnet
first wireless computer network. Used a packet-switching system, but sent the packets via radio signals. Inspired the ethernet
