Along the lines of not confusing = with != or ==.....
I frequently use "=" in online communication, but I think of it in a programming context, rather than a mathematical context.
In C, C++, and Java (I'm probably forgetting a few), the symbol "==" carries the mathematical meaning described above by NOTfnordian. For example, the expression "A == B" evaluates to true if A and B have the same value.
The symbol "=" translates into English more accurately as "gets equal to". So, if I were to say "You = Stupid", I am assigning You the value of Stupid.
I hope this helps.