If you have items in your object lists that you never look at (for example a Social Object that doesn't apply to you), or you're seeing updates in your recent activities or in your email digests about items you don't care about, you can mute those items. Muting an item hides it and its activity from your view. It's still there; you just won't hear about it anymore. (The only exception is if you're flagged on a message in a muted item, for which you will still be alerted by email based on your notification settings.)
To mute a Social Object, click , then select Mute <Social Object>.
To unmute a Social Object, from the navigation menu, select the type of Social Object you want to view. In the Show menu, select Muted, then open the Social Object. Click , then select Unmute <Social Object>
For more information, see How do I mute or unmute an item?