Most widely used textbooks for learning *characters*?

[quote=“T eacher 8”]Good topic!
Friends say book stores sell ‘frequency lists’ of characters.
(They say they are from A.p.T., a journal from N T U)
.
Fenn (sp?) 's five thousand… is a classic.[/quote]

There’s also frequency lists online. Several of them from different researchers.

I copied one into Wenlin and am studying it in order of the beginning.