Downloading YouTube videos is against YouTube's terms of service, and it is not recommended. However, if you still want to download a YouTube video for personal use, here are some ways to do it:
1.
Use a YouTube video downloader website: There are many websites that allow you to download YouTube videos by simply pasting the video link into their download box. Some popular options include KeepVid, SaveFrom.net, and Y2mate.
2.
Use a browser extension: There are several browser extensions available that allow you to download YouTube videos directly from your browser. Some popular options include Video DownloadHelper for Firefox and Chrome, and FastestTube for Chrome.
3.
Use a video downloading software: Some software programs allow you to download videos from YouTube and other video hosting sites. Some popular options include 4K Video Downloader, Any Video Converter, and Freemake Video Downloader.
It is important to note that downloading YouTube videos may infringe on the copyright of the video owner, and it may also expose your device to security risks such as malware or viruses. It's always best to watch YouTube videos online or use legitimate sources to purchase or rent the video.