What exactly do 'Characters' and 'Words' on the stats page represent?

[Apomixis]

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Characters Learned metric meaning?

What does the “characters learned” metric mean? I had thought it was a running total of the cumulative “characters” I have been exposed to. However, this week, I finished a book I was learning from and the resource said that it exposed me to over 700 characters. However, my Skritter metrics say about 448 characters in total. I thought that was odd, so I exported my Skritter lists for that resource, and 15 minutes of Matlab programming later, had a “unique character count” of 812 characters f…