 means by which
resources access and manipulate the state of the request they are
handling.

</p>
<p>

Given that all webmachine resource functions have this signature:

</p>

<span class="fwf">f(ReqData, Context) -> {Result, ReqData, Context}</span>

<p>

we should explain in detail the <code>ReqData</code> input and output
parameter.  This is a data structure used to represent the request
sent by the client as well as the response being built by the
resource.  The <code>wrq</code> module is used to access