Anyone know a great safe way to do this? Thanks.

While I have not used it for this, VLC Player can convert either from an import or a video stream to a variety of other formats, including MP3/4 and H.264; all common video formats.

Ira thanks, but do you know if does a You Tube Video to a Quiktime .MOV?

YouTube is a video stream and not a format. You can capture the stream by pressing Shift-Command-5 to launch Screenshot and selecting either the full screen or a portion off the screen to record, then playing the YouTube video. You can specify recording options in Screenshot.

ok Joe, thanks, very rusty with that, essentially recording a recording? I do tons of still screenshots, but not video yet...

This kind of new too right? Apple did not have video screenshotting, while back.

Also, there are a handful of " you tube to .mov' softwares if you google, but I'm not sure if one can trust them, hence post.

I have been using ClipGrab for some time and it works very well.

Thanks Jon/ Joe, will try clip grab.. ah... shift command 5 does not record the audio correct?

Video screenshotting has been around for a few years now. One of those features I suspect migrated from iOS to macOS. Annotating screen videos is only a year or two old however.

thanks, yet no audio....

Jon, clip grab worked good. search ok finds video in their own you tube.

Only thing: huge: 250mb... wow do four, then at Gig right?

Also, will mp4 play ok 5=10, 15 years later?

Thats whole point, only doing this for important you tube videos where not sure author will keep their site up in 5-10 years.

But have noticed over years, some videos I have kept, 5-10 years later, try to play and Apple says not supported or play with.. stuck.

There is no guarantee that if you keep any electronic media format that long that it will still be supported, or that players will still be available, or that you will still have a device capable of running the player if you still have one or even if it is in a playable format and you have a running player app, after ten years there is a substantial probability that unless you have replayed, reformatted, and resaved the files regularly (say every couple of years), the data may have begun to decay and may not be anythng you would enjoy watching. After all, 4K flat screens are so boring after you have become accustomed to 46K VR displays!

Joe this is a guitar lesson video, spent a lot of time on, so quality not critical, just 12 long. Just want it to work and play way... down road in case I have to relearn the song after investing so much time on note by note program for the song 10 hours....

And of course the you tube authors may delete their whole site in 5 -10 years.. so that is the whole point...

Boy, no problem saving a text document for 30 years, but dang.. video?.....

I would want to save that too. (I have banjo lessons like that, but psoriatic arthritis makes them rather academic.) A few suggestions for you to consider:

• convert the video into the latest and highest quality format you can find. I would suggest Apple's HEIF it is new enough that it is likely to still be around in 10 years, it yields excellent quality results, and the files are amazingly compact.
• I would store it in more than one location as a hedge against disaster.
• No HD, SSD/NVME, CD, DVD, thumb drive, etc. is likely to last 10 years but by using a variety of different media you can spread the risk. If it were me I would probably put it on two or three of the best, highest quality thumb drive I could find, prefeerabely one with both USB A and C ports. something like this or this
• Putting at least one copy in an on-line storage account such as iCloud. (Wether you like it or not, it is safe, reliable, and tightly tied to all Apple devices and likely to stay that way.)
• play and restore the copies every couple of years and be prepared to change formats if it seems wise.

Thanks, these clips will be rare, just ones I spend over hour leaning. but that converter Jon mentioned makes mp4 to desktop. I think thats fine.

I think that'll be supported long long time no? And no need hardrive backups, one at home one at bank, and .. and crashplan in cloud.

Now if these were videos I was making and put in dozens of hours.. I'd do physical media too, but not that critical.

There is still a lot of MP4 around but it is on its way out and is being replaced by newer technologies that produce higher resolution in a fraction of the file size. In ten years MP4 could well be the equivalent of cassette tape or even 8 track tape today. But then, my crystal ball is notoriously cloudy.