Underscore uses the ERB-style template syntax by default, with variables specified in-line like so: `<p><%= varName %></p>`. If you would prefer to use [Handlebars](http://handlebarsjs.com/)-style template delimiters, Underscore allows you to [customize your template formatting to taste](http://underscorejs.org/#template):
```javascript
_.templateSettings = {
  interpolate : /\{\{(.+?)\}\}/g
};
```
WordPress itself uses the delimiters `<# #>`, because PHP's asp_tags will conflict with Underscore's default `<% %>` syntax on ~5% of servers. If you're pre-compiling your templates or loading them as raw HTML rather than as PHP, this shouldn't be an issue—in those cases, you use which ever syntax feels most natural.