A few things you may not have known:

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55. "Hot off the press - everyday phrases that come from printing."

"This didn't originate as a phrase until the 20th century and means the most up-to-date news. The origin stems from the printing process called 'hot metal printing'. The Linotype machine (invented 1884) allowed printers to type on a keyboard. As they went along, the machine would cast the types right there out of molten metal (mostly lead)."

Over the last fifty years, hot metal printing has been replaced by newer processes, some of which use ink dryers in the presses. No doubt newsprint and other papers coming from the presses are warm to the touch, but the term "hot off the presses" originated in the days when molten lead was used.