word count differences

[franklekens]

How do word processors count words? And whence the discrepancies?
I have a text here, an abbreviated version of a NYT article, which MS Word says counts 1141 words, while Atlantis puts it at 1172.
And when I copy/paste the text into a plain text editor (Editpad), it says the text contains 1184 words. And when in that editor I replace all spaces with a line break so it becomes a list and I have editpad number that list, it contains 1088 items, so I would put it at 1088 words. But evens of, there are some instances where Editpad unaccountably refuses to replace a space by a line break (maybe it's some other invisible character, I don't want to find out, it's only two or three cases), so the actual tally would mount up to over 1090 by that method if I added line breaks there manually.

But most importantly for me: what keeps the word count in MS Word consistently lower than that in Atlantis? Just curious.

The number of character counts of both, no even of all three programmes do totally agree, obviously.

[franklekens]

Actually no, Editpad counts 900 characters less, but never mind.

[admin]

You can post a short sample document.

Note that toggling the "Tools | Options... > Edit > Treat apostrophes as punctuation marks" option affects the word count in Atlantis.