between goroutines.  Each send on a particular channel
is matched to a corresponding receive from that channel,
usually in a different goroutine.
</p>

<p class="rule">
A send on a channel is synchronized before the completion of the
corresponding receive from that channel.
</p>

<p>
This program:
</p>

<pre>
var c = make(chan int, 10)
var a string