When we are buiding a website or web application with the use of javascript. We have to make sure most of the people can view or use the website or web application properly. Therefore, we need to make sure we implement JavaScript in an unobtrusive manner. So that users would still be able to use it when javascript is disabled.

Christian Heilmann has found the following rules over the years developing, teaching and implementing JavaScript in an unobtrusive manner. They have specifically been the outline of a workshop on unobtrusive JavaScript for the Paris Web conference 2007 in Paris, France.

• Do not make any assumptions
• Find your hooks and relationships
• Leave traversing to the experts
• Understand browsers and users
• Understand Events
• Play well with others
• Work for the next developer

View the full article on The seven rules of Unobtrusive JavaScript.

Source: http://icant.co.uk/articles/seven-rules-of-unobtrusive-javascript/