If we're lucky, the server can respond with just a "304 Not Modified" header: we had to Whenever a resource is downloaded, the actual file itself is only one part of the This makes it perfect for deflating your CSS, JS, HTML and XML files.
The preload value of the link element's rel attribute lets you declare fetch requests in the HTML's head, specifying resources that your page will need very soon, which you want to start loading early in the page lifecycle, before browsers… I lately had to create a complex download repository for a customer. Multiple files could be selected and were compressed on the fly into a single ZIP file before being transfered to the client. First of all, I should be able to just download any file by clicking on it once (instead of right clicking, choosing where to save it, etc). And secondly, if I want to download multiple files at once, I should be able to create a JavaScript… A cross-site scripting attack could also occur if a malicious remote SWF is imported into the trusted SWF and then the remote SWF calls a javascript: URL.