"HTM" video files are computer video files embedded in the coding of a website. These videos are often encoded using Flash technology, which unfortunately makes them particularly tricky to get off of the Internet and onto your computer, but there are a few websites you can use to extract these videos from the code of a website and onto your hard drive.
Use Flash Video Downloader (see References). Copy the URL of the HTM video file you're trying to convert into the address bar at the very top of Flash Video Downloader's main page. Then, click on the "Download" file to convert that HTM video into a file that can be saved to your computer's hard drive. You can then play the file in programs like Windows Media Player or FLV Media Player.
Use Orbit Downloader (see References). Orbit Downloader is a program you install on your computer that lets you convert any HTM video to any file type you want. Open Orbit Downloader and select "Grab++" from the "Tools" menu. Enter in the URL hosting the HTM video file and then click "Download" to save the file to your hard drive in a file format of your choosing.
Use KeepVid (see References). KeepVid is a website that operates similarly to "Flash Video Downloader." Go to the KeepVid main site, type in or paste the URL of the site that is housing the HTM video into the address bar, and click "Download" to save that HTM video file into a different format on your computer that can be recognized by your favorite media playing software.