These documentation topics concern the jQuery Templates plugin (jquery-tmpl), which can be downloaded from: http://github.com/jquery/jquery-tmpl.
A template contains markup with binding expressions. The template is applied to data objects or arrays, and rendered into the HTML DOM.
Sitecore does not process default URLs such as http://somedomain.com/somefolder/. An ISAPI filter is required. A free, lite version is available here: http://www.helicontech.com/download-isapi_rewrite3.htm.
Here's an example of the regular expression required:
RewriteLogLevel 9
LogLevel debug
RewriteRule ^/(sitecore.*)$ /$1 [L]
RewriteRule ^/([^\.\?]+)/?(\?.*)?$ /$1default.aspx$2 [L]
jquery.qrcode.js is jquery plugin for a pure browser qrcode generation. It allow you to easily add qrcode to your webpages. It is standalone, less than 4k after minify+gzip, no image download. It doesnt rely on external services which go on and off, or add latency while loading. It is based on a library which build qrcode in various language. jquery.qrcode.js wraps it to make it easy to include in your own code.