title: C++: what does (a<<b) mean?
body: <p>I have a C++ header file that contains the following definitions:</p>
  
  <pre><code>#define CACHE_NUM_WAYS    (1&lt;&lt;1)
  #define CACHE_DATA_SIZE   (1&lt;&lt;8)
  </code></pre>
  
  <p>It is used as an integer in the rest of the code.</p>
  
  <p>What does it mean? And what is its value?</p>