Why does the 'X' in AJAX stand for 'XML' when AJAX almost always uses JSON??

Question

Also explain when AJAX uses xml

Answer 1

It's historical.

w3schools acknowledges this in its intro (https://www.w3schools.com/xml/ajax_intro.asp), but I think Wikipedia has a bit more to say on the subject, especially in the History section:

https://en.m.wikipedia.org/wiki/Ajax_(programming)

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