The Traghetto S. Sofia, a.k.a. the Traghetto Santa Sofia, is one of half a dozen traghetto or gondola ferry routes along the Grand Canal. (For more information on Venice's biggest transportation bargain, see our Traghetto article at Veniceforvisitors.com.)

In the video below, you'll see passengers board a traghetto on the Pescheria or Rialto Fish Market side of the Grand Canal. You can tell that most of the passengers are Venetian because they board quickly, hand their 70 centesimi euro to the boatman, move aft without waiting for their change, and turn around to face in the direction that the boat will travel after it leaves the pier. 

When the traghetto is filled with passengers, the boatman gives change to those who need it. He and the other oarsman then row the traghetto across the Grand Canal amid vaporetti, water taxis, barges, and other  traffic. The Venetian passengers remain standing, although sitting is allowed.

After the first traghetto departs, another boat from the pier across the canal arrives at the dock, its passengers disembark, and a second group of passengers get on board. It's clear from the video that a few of these passengers are tourists, because they're facing in the wrong direction and--in some cases--are sitting down (which is a wise thing to do if your balance isn't good and you aren't used to small boats).

Warning: The 70-cent fare applies only to residents. Visitors pay an outrageous two euros. (Maybe that's why tourists usually sit down during the crossing--they're so stunned by the fare that they need to catch their breath.)