When you click on a link below, you will leave our site and go to a non-government website. USA.gov does not endorse these sites. We provide the links so you can get the free software needed to view some documents or to access audio and visual files on some websites.
Portable Document Format (PDF)
Some documents on government websites are in Portable Document Format (PDF). PDFs allow you to view publications in their original format regardless of what type of computer, browser, or operating system you use to access the Internet. In order to view, navigate, and print PDF documents, you'll need the free Acrobat Reader software. Instructions and a troubleshooting guide are available on the Adobe website. If you use a screen reader, you can download Adobe software to make PDF files more accessible.
Real Video and Real Audio Files
These files, which have the extension (".ram", ".ra", ".rm", ".rmm", ".rp", ".rms", ".rt", ".rmj"), require installation and use of the RealPlayer software. This free software is available from RealNetworks. The Real file format allows you to "stream" audio and video files, which means that you begin hearing and seeing the files without having to wait for the entire file to download. To hear audio on your computer, your system must also have speakers or earphones and a sound card.
RSS (Really Simple Syndication) Aggregators
RSS feeds, (which have the extension ".xml", ".rss", ".sfm", ".cfm", ".rdf", ".aspx", or ".php"), require installation and use of RSS aggregator software. An RSS aggregator allows you to subscribe to an RSS feed. There are many aggregators available; some are free and some are available for sale. RSS feeds are commonly used on weblogs (blogs), news websites, and other places with frequently updated content. An RSS aggregator gathers material from websites that you tell it to scan, and it brings new information from those sites to you. It's a convenient format because it allows you to view all the new content from multiple sources in one location on your desktop.
These files have the extension ".xml" and ".php" and require installation and use of podcatching software (a type of aggregator). This software is available for free from Juice (for PC, Mac, and Linux), iTunes (PC and Mac), and jPodder (PC). There is much more podcatching software available. Podcasting is a method of publishing audio broadcasts via the Internet, allowing users to subscribe to a feed of new audio files, usually MP3s. Listeners may subscribe to feeds using podcatching software, which periodically checks for and downloads new content automatically. Any digital audio player or computer with audio-playing software can play podcasts.
Other Audio Files
Some audio files on government websites have an ".au" extension. These sound files can be played using a standard sound player bundled with your computer's operating system, for example, Windows Media Player for Windows, SoundMachine for the Macintosh, and XPlayGizmo for Unix. To hear audio on your computer, your system must also have speakers or earphones and a sound card.