I had put the tutorial offline for a while to correct errors. These have now been removed. However, if you find some, please do let me know. Enjoy!
Web pages made using only HTML are somewhat static with no interactivity and negligible user involvement. Interactive pages can be described as those that understand and process user behaviour (actions) like mouse movements, mouse button clicks, HTML button clicks etc.
HTML tags are just instructions on document layout and structure; the display of the document in the window is dependent on the browser. Interactive pages cannot be built with only HTML, we need a programming language. Further, since the response time to user actions should be quick, the programming language has to be embedded in the browser itself. (Programs residing on servers can not bring about interactivity due to the time taken for sending the user input and receiving the response.)
VBScript: Implemented only under Internet Explorer, this client-side language is similar to BASIC. It is commonly used in ASP technology.
PerlScript: Similar to the Perl Language. Not very well supported by browsers.
John D. Kubiatowicz, a Professor at the University of California at Berkeley, estimated that the Amazon Kindle ebook reader gains 10^-18 grams when it's fully loaded with books. The calculation is based on the number of electrons that are actually used to store the books! [more...]