What Javascript Can't Do.

While there are many things that Javascript can do to enhance your visitor's experience of your web pages there are also a number of things that it can't do. These restrictions are not just randomly imposed on Javascript but have to do with where Javascript gets run, how the web and browsers work, and the security issues that may ensue were Javascript allowed access to perform certain functions. As there are a number of things that were not expected to have security implications which have turned out to be security issues there are also a number of things that earlier browsers permitted Javascript to do that the more modern browsers no longer permit.