Just curiosity, but does "Jack" and "John" are the same name? Because I heard some people call JFK to Jack Kennedy instead of John.
"Jack" and "John" are different names. John F. Kennedy is sometimes called JFK, with the first letter of his first, middle, and last name being used to create this acronym. JFK is only used to refer to him and not his wife, who was named Jacqueline (Jackie) Kennedy Onassis and did not have the same initials in her name (JKO).
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