"The tragedy of common sense
it that it is not
very common."
(Albert Einstein)

"Politically correct Christianity
is tolerated but despised.
Full Gospel Christianity is
respected but persecuted."
(Unknown)

"If you marry the Zeitgeist
you will soon become widow."
(Goethe)

"To reach the source of a river
you must swim upstreams."
(Stanislaw Jerzy Lec)

"I note that all those,
who are positive to abortion
already are born."
(Ronald Reagan)

Punch card codes

 

As the reader can see, each (vertical) column on this punch card has 12 positions, which from bottom-up are; 9 rows numbered (9-1), one row numbered 0 and two unmarked rows above, which are usually called X and Y (thus 9 at the bottom and X uppermost). Each character is encoded using 0-3 punches (holes) on the card. Zero (0) holes, i.e. no hole, in a column, represents a "space".

The holes in the same vertical column below the plain language character (letter, figure etc) are coding for this character.

The coding on punch cards is a special type of coding, adapted for such cards (for the informed reader I can mention that it is not ASCII code or something similar). It is called EBCDIC (Extended Binary Coded Decimal Interchange Code). Punch cards intended for storing program codes used a simplified code (EBCD, a subset of EBCDIC), which could only code for capital letters and other characters used for programming. For this reason, programs in those days were always written in capital letters.

The above table shows how punch cards intended for programming were coded. To the extreme left we have vertically and downwards "-, Y, X, 0" and and on top, horizontally, from left to right, "-, 1, 2,... 6-8, 7-8". Dash ("-") means no holes punched. The upper left corner in the table, dash-dash (the empty square), means no holes punched in this column, i.e. "space" (between words).

Let me give two examples:

1. The letter "W" (the framed column marked with an arrow in the first picture above). The code is, according to the table "0-6" (holes at positions zero and six). If we look at the punch card above, we can see that below "W" (in the frame) we have one hole punhced in the 0-line and one hole in the 6 line. The column appears a bit warped, which is probably caused by the photo being taken at a slight angle.
2. Left parenthesis "(". The code is Y-5-8 (i.e. 3 holes punched). There are 2 left parentheses in the plain text, If we look on the card under the "(", we see holes punched in these two columns in positions Y (just below the plain text) and 5 and 8.

 

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