The industrial revolution had driven forward the mechanization of many tasks, and this included weaving. Punched cards controlled Joseph Marie Jacquard's loom in 1801, where a hole punched in the card indicated a binary one and an unpunched spot indicated a binary zero. Jacquard's loom was far from being a computer, but it did illustrate that machines could be driven by binary systems.
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Punched cards and paper tape are obsolete WORM media. Although any unpunched area of the medium could be punched after the first write of the medium, doing so was virtually never useful. Read-only memory (ROM) is also a WORM medium. Such memory may contain the instructions to a computer to read the operating system from another storage device such as a hard disk.
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The BCD code is the adaptation of the punched card code to a six-bit binary code by encoding the digit rows (nine rows, plus unpunched) into the low four bits, and the zone rows (three rows, plus unpunched) into the high two bits. The digit zero (a single punch in row 0) is usually handled specially in some way, and the digit code was extended to values 10 through 15 by combining a digit in the range 2–7 with a punch in row 8. IBM applied the terms binary-coded decimal and BCD to the variations of BCD alphamerics used in most early IBM computers, including the IBM 1620, IBM 1400 series, and non-Decimal Architecture members of the IBM 700/7000 series. Among the vendors using BCD were Burroughs, Bull, CDC, IBM, General Electric (the computer division was purchased by Honeywell in 1969), NCR, Siemens, and Sperry-UNIVAC.
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This system used Mylar cards the size and shape of a standard IBM punched-card, so the microcode could be changed using a keypunch. Each card held 720 bits, and the total microcode consisted of 4032 60-bit words. The Mylar "encased copper tabs and access lines." A hole punched at a specific location removed the copper tab and encoded a zero, unpunched locations were read as ones.
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In a passenger car, he meets a spirited girl and a know-it-all boy. The train picks up a boy named Billy, who also declines to board, but changes his mind, and the boy pulls the emergency brake to allow Billy to board, which is noticed by the conductor. As Billy sits alone in the train's observation car, hot chocolate is served in the passenger car, and the girl stows away a cup for Billy. As she and the conductor cross to the dining car, the boy notices that she left her unpunched ticket, but loses hold of the ticket between the cars when he attempts to return it.
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Eventually the governor rescinded this degree and all silver coins were traded based on their weights and intrinsic value again rather than their nominal value. On 5 March 1863, the colonial governor of French Cochinchina had made silver French francs and copper centime coins legal tender for commercial transactions within the territory. Then the French colonial governor had issued a degree which officially valued the 5 francs coins at 90% of a piastre, but its intrinsic value was actually 93% of a Piastre, which allowed for abuse by merchants, which made this another decree that had to be rescinded. Eventually the French government released the unpunched 1 centime coins into circulation in French Cochinchina alongside other metropolitan French coins such as the centimes and francs.
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After the unpunched 1 centime and other French franc coins were introduced they would see little circulation with the local population, while the merchants still preferred the Mexican peso for their trade. The governor of French Cochinchina established a study group to design coins which would be accepted by the local population on December 24, 1878 by decree. This study group submitted designs, denominations, metals and weights of the sapèque, 1 cent, 10 cents, 20 cents, 50 cents, and piastre coins with the text "Cochinchine Française" on them, these designs were officially accepted by decrees issued on April 7 & 22, 1879 by the governor. All coins except for the 1 piastre coin were introduced, the piastre would only be introduced as part of the French Indochinese piastre later and Spanish and Mexican silver coins served as the piastres in Cochinchina.
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When electromechanical teleprinters were used as computer output devices, one or more null characters were sent at the end of each printed line to allow time for the mechanism to return to the first printing position on the next line. On punched tape, the character is represented with no holes at all, so a new unpunched tape is initially filled with null characters, and often text could be "inserted" at a reserved space of null characters by punching the new characters into the tape over the nulls. Today the character has much more significance in C and its derivatives and in many data formats, where it serves as a reserved character used to signify the end of a string,"A string is a contiguous sequence of characters terminated by and including the first null character" — ANSI/ISO 9899:1990 (the ANSI C standard), section 7.1.1 often called a null-terminated string.
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