Does '!=' equivelent to 'is not'

[Terry Reedy]

>> Saying a flat "no" alone, without qualifying your statement is
>> generally interpreted as rude in English...  It's kind of like how you
>> talk to children when they're too young to understand the explanation.
>> Yucky.
> 
> I didn't meant to be rude at all - and I apologize to Mr. Lie. The 
> explanation for such strong "No" was in the paragraph below it (the idea 
> was to say: "No to this, yes to that")

As a very much native English speaker I disagree that 'No' is 
necessarily rude.  I wish I could more often get such a clean answer to 
my questions from my child.