In the pre Internets era some newspaper writers were paid (what's that?) on a per column inches basis. I.e. the amount of material that got published would be used to determine their pay check. Editors would take the bound copy of last month's issue and use a ball of string to measure out all the writer's stories for that particular time period. If all the fellow's stories used up 35 inches of string and if his pay rate was $10 an inch -- wait just a dang minute, let's call it a buck an inch -- you do the math. (It doesn't take a professional trend-spotter to know that Americans are going to get used to smaller paychecks.) That's how the part time editorial employees got to be called stringers.
In the age of telegraphed news stories there was no word with three x's in a row. (That was before adult movies started to run ads in newspapers.) So the telegraphers got in the habit of designating the end of a story by inserting XXX, which was the Roman numeral for "thirty."
Speaking of which . . .
To be continued . . . (but not necessarily tomorrow.)