Jen and Camille: UNIBAC, ARPANET, Packet Switching, Punch Card

• The UNIVAC I (UNIVersal Automatic Computer I) was the first commercial computer produced in the United States
  
• first UNIVAC I was delivered on June 14, 1951. From 1951 to 1958 a total of 46 UNIVAC I computers were delivered, all of which have since been phased out
  
• designed by J. Presper Eckert and John Mauchly
  
• used 5,200 vacuum weighed 29,000 lbs, consumed 125 kW, and could perform about 1,905 operations per second. The complete system occupied more than 35.5 m² of floor space
  
• In 1952, it successfully predicted the outcome of the 1952 presidential election during a televised news broadcast
  

• The ARPANET (Advanced Research Projects Agency Network) developed by ARPA of the Department of Defense, was the world's first operational packet switching network, and the predecessor of the global Internet
  
• Packet switching now the dominant basis for both data and voice communication worldwide, was a new and important concept in data communications 
  
• Previously, data communication was based on the idea of circuit switching, as in the old typical telephone circuit, where a dedicated circuit is tied up for the duration of the call and communication is only possible with the single party on the other end of the circuit
  

Packet switching is a network communications method that splits data traffic (digital representations of text, sound, or video data) into chunks, called packets, which are then routed over a shared network. To accomplish this, the original message/data is segmented into several smaller packets. Each packet is then labeled with its destination or connection ID. In each network node, packets are queued or buffered, resulting in variable delay and throughput, depending on the traffic load in the network. This contrasts with the other principal paradigm, circuit switching, which sets up a specific circuit with a limited number of constant bit rate and constant delay connections between nodes for exclusive use during the communication session.

• A punch card (aka IBM card) is a piece of stiff paper that contains digital information represented by the presence or absence of holes in predefined positions 
  
• widely used throughout the 19th century for controlling textile looms and in the late 19th and early 20th century for operating fairground organs and related instruments 
  
• was used through the 20th century in unit record machines for input, processing, and data storage, early digital computers used punched cards as the primary medium for input of both computer programs and data, with offline data entry on key punch machines (some voting machines use punched cards)
  
• Punch cards were first used around 1725 by Basile Bouchon and Jean-Baptiste Falcon as a more robust form of the perforated paper rolls then in use for controlling textile looms in France
  
• From the 1900s, into the 1950s, punch cards were the primary medium for data entry, data storage, and processing in institutional computing