Historically, web browsers supported limited file formats; the browser manufacturers' were able to support more formats using "plugins," small, special purpose programs that ran inside the web browsers.
Over time, those web browser manufacturers began to see those plugin programs as security risks and have phased out or are phasing out support. Additionally, new Web standards are helping to provide direct support in the browser for some of those file types.
USPTO believes all the file formats we use on our website are well supported by current web browsers and operating systems. If you run across something that you can't view, it would help us help all our website visitors if you tell us about it.
Your web browser's product page and help menu will also have additional information specific to that browser.