title: What is the purpose of the bitwise inclusive OR operator?
body: <p>From what I understand, the bitwise inclusive OR operator compares every bit in the first and second operand and returns 1 if either bit is 1. Bjarne Stroustrup uses it like this (ist being an istream object):</p>
  
  <pre><code>ist.exceptions(ist.exceptions()|ios_base::bad_bit);
  </code></pre>
  
  <p>I haven't really worked with bits a lot in programming, should it be on my to-do list to learn? I understand that if I had an int and the value was 9, the binary would be 00001001, but that is pretty much it. I do not understand why he would use this operator in the context that he used it in. </p>