By logging into gmail before going to YouTube, you can take advantage of its features, for instance, uploading videos, commenting on people’s videos, and saving videos in your playlist.
You need to sign in to Google through Gmail to be able to create a YouTube Playlist. This is a great way to organize your own videos (e.g., if you have 25 videos in your YouTube library, 15 of them are related to educational technology, and 10 of them are related to penguins, you can create to separate playlists for your viewers). You can create playlists with any videos on Youtube, including your own.
YouTube Playlist is a free tool that allows you to collect and organize videos around specific topics or interests.