You may have several options when it comes to downloading videos that you find online. You need videos for many reasons as sometimes a particular video may be something that you may want to keep referring to every time. But if you rely upon Youtube or another website that carries it, then you will not be able to always guarantee that it will be available when you need it.
So the only way one could guarantee that a particular video is always going to be accessible to them is by downloading them to their own devices. There are several ways you could download videos and there are different device types and sizes you could be downloading them on.
One of the problems that you will come across when trying to download a video that you love is that of actually finding a website that can facilitate it for you. Not every website will have all types of videos that you would love to add to your collection of those downloaded on your device.
There are plugins for browsers available to help you download videos from Youtube and similar other websites. And if you are using a mobile device to download then you will need an appropriate application to download your videos. A good website you could refer to for a range of videos that you could download is DownloadSite. Visit it and see which one of the videos published would be something you would be interested in downloading.