The sequence of letters, Etaoin Shrdlu, appeared occasionally in newspapers many years ago, leading some to conclude that these letters were the name of some mysterious person. The reason for its appearance, however, was no mystery: Etaoin Shrdlu are the letters produced by running the finger down the first two vertical rows of the Linotype machine keyboard. The Linotype was the brand name for a printing device invented by Ottmar Mergenthaler in 1886 and first used in the New York Tribune. The text line was cast with molten lead when the operator keyed in and finished a line of text. Etaoin Shrdlu was used as a temporary marking slug or to indicate that a typographical mistake was made that required resetting of the cast. Linotype operators used this sequence because it was so easy to make on the keyboard. Sometimes the sequence inadvertently made it into print. Linotype typesetters were ubiquitous in the newspaper and industry (and were even used on the battlefields of WWI) up to about 1960, after which they were replaced with photocomposition. Etaoin Shrdlu likewise disappeared from print, except for the name on the occasional novel, comic strip, or science fact book.
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