Difference between titanium and titanium dioxide electrode
Used as an anode, a normal untreated piece of titanium metal will "anodize", forming a non-conductive titanium dioxide coating.  In my experience, the current through a large untreated titanium sheet anode drops below the milliamp level in under a minute.  

But there are a variety of electrically conductive but oxidation resistant micron-scale coatings that can be formed onto titanium, including platinum (a "platinized titanium anode"); conductive oxides of common metals like Pb or Sn (lead dioxide or tin oxide); or conductive oxides of rare metals like Ir, Ru, or Ta (a "mixed metal oxide anode").  There are some decent electron microscope microstructure photos in Umicore's promotional catalog.  

The advantage to using a "valve metal" like titanium or aluminum as the substrate on a coated anode is if part of the fancy conductive coating flakes off, the bare titanium just anodizes and stops conducting, rather than getting eaten away and dissolving into the electrolyte.