Explanation of <script type = "text/template"> ... </script>

I just stumbled upon something I've never seen before. In the source of Backbone.js's example TODO application (Backbone TODO Example) they had their templates inside a <script type="text/template"></script>, which contained code that looks like something out of PHP but with JavaScript tags. Can someone explain this to me? Is this legit?

[yamadar]

By setting the type to "text/template", it's not a script that the browser can understand, and so the browser will simply ignore it. This allows you to put anything in there, which can then be extracted later and used by a templating library to generate HTML snippets.

[iR3]

#sendagayarb でテンプレートの話中 これが使えるかもと