TWiki expands the following variables enclosed in % percent signs:

<table border="1">
  <tr>
    <th> Variable: </th>
    <th> Expanded to: </th>
  </tr>
  <tr>
    <td><code>%<nop>WIKIHOMEURL%</nop></code></td>
    <td> The base script URL of TWiki, link of Home icon in upper left corner is <b>%WIKIHOMEURL%</b></td>
  </tr>
  <tr>
    <td><code>%<nop>SCRIPTURL%</nop></code></td>
    <td> The base script URL of TWiki, is <b>%SCRIPTURL%</b></td>
  </tr>
  <tr>
    <td><code>%<nop>PUBURL%</nop></code></td>
    <td> The base public URL of TWiki, is <b>%PUBURL%</b></td>
  </tr>
  <tr>
    <td><code>%<nop>ATTACHURL%</nop></code></td>
    <td> The attachment URL of the current topic, is <b>%ATTACHURL%</b><br /> Example: If you attach a file you can refer to it as <code><b>%<nop>ATTACHURL%/image.gif</nop></b></code></td>
  </tr>
  <tr>
    <td><code>%<nop>WIKIWEBMASTER%</nop></code></td>
    <td> The email address of the Wiki webmaster, is <b>%WIKIWEBMASTER%</b></td>
  </tr>
  <tr>
    <td><code>%<nop>WIKITOOLNAME%</nop></code></td>
    <td> Name of wiki tool, is <b>%WIKITOOLNAME%</b></td>
  </tr>
  <tr>
    <td><code>%<nop>WIKIVERSION%</nop></code></td>
    <td> Wiki tool version, is <b>%WIKIVERSION%</b></td>
  </tr>
  <tr>
    <td><code>%<nop>USERNAME%</nop></code></td>
    <td> Your login username, is <b>%USERNAME%</b></td>
  </tr>
  <tr>
    <td><code>%<nop>WIKIUSERNAME%</nop></code></td>
    <td> Your Wiki username, if defined in <span style="background:"><font color="">TWiki Users</font></span><a href="http://LOCATION/TWikiUsers">?</a>. Same as %<nop>USERNAME% if not defined. Is <b>%WIKIUSERNAME%</b> </nop></td>
  </tr>
  <tr>
    <td><code>%<nop>WEB%</nop></code></td>
    <td> The current web, is <b>%WEB%</b></td>
  </tr>
  <tr>
    <td><code>%<nop>TOPIC%</nop></code></td>
    <td> The current topic name, is <b>%TOPIC%</b></td>
  </tr>
  <tr>
    <td><code>%<nop>DATE%</nop></code></td>
    <td> Todays date, is <b>%DATE%</b></td>
  </tr>
  <tr>
    <td><code>%<nop>INCLUDE:"file.ext"%</nop></code></td>
    <td> Server side include, includes the text of a file. The default directory is the current Wiki web. Example: <code><b>%<nop>INCLUDE:"../Know/TopicName.txt"%</nop></b></code></td>
  </tr>
</table>