Angular paramMap vs queryParamMap? : <p>What are the different paramMap and queryParamMap?</p>

<p>Angular website says 
paramMap -  An Observable that contains a map of the required and optional parameters specific to the route. The map supports retrieving single and multiple values from the same parameter.</p>

<p>queryParamMap - An Observable that contains a map of the query parameters available to all routes. The map supports retrieving single and multiple values from the query parameter.</p>

<p>I would like to know when I have to use with examples.  </p>

<p>Thanks</p>
