Stack Exchange network consists of 175 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.
Is there a difference in usage between "he isn't"/"she isn't" and "he's not"/"she's not"?
I think "he's not" and "she's not" are stronger because they put more emphasis on the word "not" than "he isn't" and "she isn't" do.
No there is not. Or no there's not. :)
Isn't is a contraction of "is not".
He's/she's is a contraction of "she is/he is".
They are just different ways of writing the same sentence.
Both are acceptable and both have the same initial meaning. Similar to "we're not" and "we aren't" because both mean "we are not." The English language is very confusing, in this case, there are multiple ways to say the same phrase.