user62458: A lot of tutorials are about how to control Arduino through WiFi, but I need my Arduino to send information about motion sensor activity to a server. Is that possible?

user4143: 
Can you make Arduino Uno send information through a WiFi module to a server?

Yes, I can.
The simplest way is through an HTTP "GET" request. Every time you request a web page (and there are plenty of examples of that) you are sending data to the server to tell it both what web page to get (/foo/bar.php) and what data to submit to that web page (?baz=4).
It's then up to you to craft that GET request, such as:
GET /foo/bar.php?baz=4 HTTP/1.1
Host: example.com
Content-length: 0

and write the PHP web page (or whatever language you prefer to write web pages in) to do something meaningful with the "baz = 4" parameter.

62458: <p>A lot of tutorials are about how to control Arduino through WiFi, but I need my Arduino to send information about motion sensor activity to a server. Is that possible?</p>
 4143: <blockquote>
  <p>Can you make Arduino Uno send information through a WiFi module to a server?</p>
</blockquote>

<p>Yes, I can.</p>

<p>The simplest way is through an HTTP "GET" request. Every time you request a web page (and there are plenty of examples of that) you are sending data to the server to tell it both what web page to get (<code>/foo/bar.php</code>) and what data to submit to that web page (<code>?baz=4</code>).</p>

<p>It's then up to you to craft that GET request, such as:</p>

<pre><code>GET /foo/bar.php?baz=4 HTTP/1.1
Host: example.com
Content-length: 0
</code></pre>

<p>and write the PHP web page (or whatever language you prefer to write web pages in) to do something meaningful with the "baz = 4" parameter.</p>
