You can choose to make the channels that you subscribe to public or private. By default, all settings are set to private. 

• Private: When your subscriptions are set to private, no other users can see what channels you subscribe to. Your account does not show in a channel's Subscribers List, even if you are subscribed. 
• Public: When your subscriptions are set to public, other users can see what channels you subscribe to. Your subscriptions are listed on your channel page, and your account is listed in the Subscribers List for any channel you subscribe to. 

Make your channel subscriptions public or private

1. Sign in to YouTube.
2. Click your account icon in the top right.
3. Click Settings or . 
4. In the left menu, select Privacy.
5. Under "Likes and subscriptions," check or uncheck the box for Keep all my subscriptions private.

* Nguồn: Youtube