What does “traffic” mean?

As heard from Martin Nisenholtz at the OMMA Global conference last week, Twitter drives 10 percent of the New York Times’ traffic.

What does this mean?  Is it 10 percent of page views?  Unique visitors?  Visits?  Page views per visit?  Visits per unique visitor?

Nisenholtz, the senior VP of the NYT’s digital operations, reportedly said that the NYT’s Twitter account has 1.8 million followers and growing.

OK.  That’s a nice big number.  But it doesn’t tell you anything about whether any of those followers – or anyone who got to the site through Twitter – really engaged with the site.  How many followers go to the NYT site?  How often?

I have no doubt Twitter is an important source of traffic – however it’s defined – for the NYT and other news sites.  Let’s take the time to dig deeper so we really understand Twitter’s impact.