Support web browser
Besides, the web browsers continues updating and step by step they give support at new rules from these programming languages. We should take specially care, because if some work in a broweser maybe in other not (specially in Internet Explorer ¬¬).
So, when we’ll use new code, any programming language, we should be secure ourself about his support in each web browser and his versions.
On this way we avoid to search among thousand pages from researcher, without to be secure that the information which we are seing is updated..