title: Difference between Laravel Collection methods has() and contains()
body: <p>I'm having problems understanding the difference between the Laravel Collection methods <code>has()</code> and <code>contains()</code>.  </p>
  
  <blockquote>
    <p>The contains() method takes a single value, a key-value pair of parameters or a callback function and returns a boolean value of the value is present in the collection or not.  </p>
  </blockquote>
  
  <p>So basically, it returns a boolean based on the existence of a value.</p>
  
  <blockquote>
    <p>has() - returns a boolean value if a key value is present in a collection or not.</p>
  </blockquote>
  
  <p>And this also returns a boolean based on the existence of a value?</p>
  
  <p>Somehow I don't get the difference of them.<br>
  I hope someone can explain it to me or share some useful links, I'd be really grateful.</p>