You need a Google Account to sign into YouTube. A Google Account works across all Google products (e.g. Gmail, Blogger, Maps, YouTube, and more).

If you've signed into any of these products before, you already have a Google Account. To sign in, enter the email address you entered on those products (if you use Gmail, it's your Gmail username). If you don't have a Google Account, you can create one on YouTube.

Here are a few important things to remember about Google Accounts and YouTube:

• You sign into YouTube with your Google Account. To sign in to YouTube, enter your Google Account email and password. After signing up for YouTube, if you sign in to your Google Account on another Google service, you'll be automatically signed in when you visit YouTube.
• Deleting your Google Account will delete your YouTube data, including all videos, comments, and subscriptions. Before you can delete your Google Account, you will have to confirm that you understand that you're permanently deleting your data on all Google services, including YouTube.

When you sign into YouTube with your Google Account, you can take advantage of many YouTube features:

• Like videos
• Save Favorites
• Subscribe to channels
• Watch Later
• Watch History
• Flag videos

YouTube will also be able to personalize video recommendations based on the videos you’ve liked and watched and your subscriptions.

Unless you create a channel, you won't have a public presence on YouTube. Your activity is fully private. If you'd like to upload your own videos, comment on videos, or create playlists, you can create a YouTube Channel at any time.

* Nguồn: Youtube