Trouble accessing my MKV download on MacPro

[grandpa]

I am brand new to MKV and I am old so please excuse my ignorance (better word than stupidity). Through MKV online help I downloaded a movie to my new Macbook Pro. It put the movie in a folder and when I try to use IMovie to access the folder it says there is no content in the folder. However, the folder shows that it has 5.5 gigs in it. I can't figure out how to access the movie so I can watch it at a later date. I can't find any manual or instructions anywhere for MKV so I am reverting to this forum for help. Thank you in advance to anyone who tries to help me.

Grandpa

[Woodstock]

Do you have VLC (available from videolan.org) for the Mac installed? It is one of several programs that will play MKV files that is available for the Mac.

iMovie does not understand the MKV format, so it isn't going to display MKV files.

There are options, both paid and free, for converting MKV files to iMovie supported formats, such as MP4. One of the most popular is Handbrake (available at handbrake.fr), which reads a number of formats, and will transcode them something iMovie (and iTunes, QuickTime, and Apple devices) will play.