TAAG ka full form hai Trains At A Glance, jo ki Railway ka Annual Timetable ka naam hai.. har saal print hoti hai, is saal abhi tak nahi hua.. ab regular trains jab start hogi tab hi hogi direct. is Yearly timetable me agle 1 saal ke liye sab trains ka timetable print rehta hai.. hum railfan isko TAAG hi bolte hai...Hope now its clear as what is TAAG.