In Internet culture a lurker is typically a member of an online community who observes, but does not actively participate.

1234346_424668054308268_504076479_n – From Wikipedia

The majority of social media users are lurkers in some way, shape or form; whether you’re waiting for the bus and quickly reading your Twitter feed or sitting on your couch and scrolling through your Facebook timeline. Anytime you’re surfing your social channels without creating content or engaging in conversation, you’re lurking.

What does this mean from a brand perspective?

Even though the lurker isn’t engaging with your brand, they’re still consuming the content that you’re putting out there. Just because they’re not participating in online conversations about your content, doesn’t mean they’re not participating in offline conversations about your content.