title: Erlang: include module and call functions
body: <p>I am going through Erlang code.</p>
  
  <pre><code>tes_lib:check_operational(Config)
  </code></pre>
  
  <p>The above code is present in a module called <code>Sample.erl</code>.</p>
  
  <p>I am new to this language. My question is that I cannot see any include statement for the module <code>tes_lib</code> in <code>Sample.erl</code>. So, how come <code>Sample.erl</code> is able to call the function <code>check_operational</code> using <code>tes_lib</code> module?</p>
  
  <p>I thought that it should be like Java, where we first import the class and then call the function.</p>