title: STL performance O(ln(n)) questions
body: <p>Please, can someone explaine this:</p>
  
  <p>If documentations says that STL std::vector finding element speed performace = O(ln(n)), 
  what does it mean.</p>
  
  <p><code>O(ln(n))</code> - what is "<strong>O</strong>", where I can read about that?</p>
  
  <p>And where I can read about performace of other STL containers preformance</p>
  
  <p>Thank you very much</p>