Plugins extend your online experience by allowing additional content besides text and images. The most common ones are usually «Flash», «Java» and some video/media players like «QuickTime». Also PDF compatibility is provided via these extensions, mostly with built-in solutions or the popular «Adobe Acrobat Viewer». Every browser and operating system has various possibilites which can be extended by installing other products. However, modern mobile browsers like «Safari» for iPhone don't have any installed, which results in limitations on certain web pages.