Adobe has released a new major version of its free Adobe Reader, the program that allows you to view PDF files. A significant new security feature is sandboxing. For those not familiar with the concept, the main program interacts with the outside world (i.e., the operating system) through a second, supervisor program. The supervisor typically just echoes the requests straight to the operating system, but it also ensures that any unauthorized or unsafe requests are denied. So even if a vulnerability is discovered and successfully exploited, the sandbox mechanism will prevent it from doing anything. Note that using the regular Adobe Reader update function will not get you version X—you’ll need to go to the download page and manually start the installation.