Javascript does anything that involves non-static data such as calculations. It is also the client side language and has the ability to read and change elements from both Css and Html. JCR or Jcodereview can be used to review any source code as well as Javascript. The purpose of JCR is to help standardize coding and ensure good coding design. Some added benefits are that it can help point out bugs in the coding and help teach new developers good and bad technique. With all the information, coding languages and even the many browsers the internet can be a confusing place. W3C, World Wide Web Consortium, has set out to standardize some of the features of the web. They are an internationally based community that works with other organizations and the public to create some standards on the web. The organization is led by C.E.O Jeffrey Jaffe and Tim Berners-Lee. In addition, they want to make the web a place that anyone can access. According to World Wide Web Consortium they see the web as both a "giant repository of linked data and as a giant set of services that exchanges messages."
That defines it