Web Science/Part1: Foundations of the web/Dynamic Web Content/Ajax and the XMLHttpRequest class/quiz

{What is true about using JavaScript for issuing an HTTP request from some webpage?} + Usually only HTTP requests to the domain from which the webpage that contains the calling JavaScript was downloaded are possible - It is possible to make HTTP requests to other servers if they run on port 433 + It is possible to make HTTP requests to other servers if they have a cross origin resource sharing policy + It is possible if the domain from which the webpage that contains the calling JavaScript was downloaded is white listed in the Access-Origin Header field of the server response. - If not allowed the browser will prevent JavaScript from making the HTTP request. - the repsonse has to be in JSON (JavaScript object notation)
 * interestingly the request is made and only the response is dropped (this makes sense otherwise the Access-Control header of the response could not be processed by the browser SEND MAIL TO CHRISTOPH)
 * No, the response can be in any format.

{Why is JavaScript useful for the World Wide Web?} + It enables more interactive websites + It can take loads of traffic from the web server or the web server's backend - It can help websites to better communicate with search engines and provide metadata like RDFa - Without JavaScript, the structure of web content could not be completely seperated from layout and formatting + It can help to easily make asynchronous HTTP requests to a web server
 * even though HTML allows for input fields and text areas JavaScript increases the amount of interactivity
 * yes for example if data needs to be sorted this can easily be done by the client
 * No indeed search engines frequently ignore JavaScript
 * JavaScript does not aim to support people to separate structure from layout and formatting
 * This is useful since a webpage does not have to be assembled at the server which blocks but can rather be asynchronously assembled on the client side.

{What are the advantages of JavaScript libraries?} + They provide an API that will work on almost any browser - They make JavaScript more powerful
 * The most popular browsers and many different versions are supported by these libraries.
 * No, they don't change the expressiveness of JavaScript at all

{Which of the following are JavaScript libraries} + jQuery - PHP - Java + mootools + Prototype - Netscape