<p>Is it possible for a web server to know which <em>type</em> of device request has been received from?</p>

<p>For example, can a create a website which shows different contents if request came from a computer (Firefox) and something different if it came from iPhone?</p>

Check the
```
User-Agent
```
in the Request Header
For full details on HTTP headers, see the specifications at
http://www.w3.org/Protocols/
.