A few things you may not have known:

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40. The term "hot off the press" originated in the days when newspapers used a process called

"hot metal printing," not because the newsprint itself was hot when it came off the presses.

In "hot metal printing" molten lead was poured into a "Linotype Machine" which cast the molten lead into individual lines of type (hence the name of the machine). The lines of cast lead type were grouped together, inserted into the press, inked and used to imprint the pages.