He pops up here and there, directing traffic at street corners, helping kids off school buses, sweeping up hair at barbershops. Wherever he is, so too is his bicycle and signature bright orange and yellow safety jacket, complete with silver reflective stripes. Who is he? A crossing guard? City employee? No, a neighborhood volunteer. If you don’t know him, and you really should, just ask. Pretty much everybody knows him. “That’s Tata,” is the response with a knowing shrug.