title: Most used STL algorithm, predicates, iterators
body: <p>I cannot find this question on stackoverflow. But I am wondering how people use STL (No fancy boost)... just an ol' fashion STL. Tricks/tips/mostly used cases acquired over many, many years... and perhaps gotchas...</p>
  
  <p>Let's share it...</p>
  
  <p>One tip per answer...with code example -- </p>
  
  <p><strong>Edit</strong> is it such a bad question as it resulting in downvotes?</p>