All members have a place to check notifications on the site. Notifications alert you to new activity surrounding actions you or others make on the site.
If you are receiving too many emails or notifications surrounding a certain post or question on the site, you can unfollow the post or question. This will stop all emails and notifications surrounding that content unless you decide to follow it again.
To unfollow a post or question that you interacted with, select the little circle in the top right corner on the post itself, or on your notifications page. Then select unfollow. This will stop all notifications.
Should you decide to follow it again, just go to that post or notification and select the little circle in the top right corner and select follow. This will re-activate notifications for that post or question.