While sites like Youtube and Vimeo offer the convenience of watch as you download videos, sometimes you need to save these videos for offline playback as in when you have a slow Internet connection or their use in offline presentations or save them on your handheld devices to watch them while you are on the road. Youtube has many videos that are hours long which means you may pause the videos and resume watching at a later time. Therefore, offline watching is more appropriate for such a video.
While there are many sites that offer this service with my favorite being the no frill http://peggo.co, sometimes you need more flexibility such as downloading videos at higher resolutions beyond 720p. The site below offers a lot of these extra features including downloading 4k videos.
https://www.4kdownload.com/
A word of caution about downloading and installing free programs that offer video downloading. These types of programs are often ripe with malware. I recommend that you use these free downloaders inside virtual machines or if you are a heavy downloader, have a dedicated machine for this purpose, one that is not used to store any important data.
