On all the plots of a notebook I have to put a vertical line at the same place. I thus use the GridLines option for Plot along with the option GridLinesStyle. To get it done easily I use the function SetOption for Plot: SetOptions[Plot,GridLines->{{1},{}},GridLinesStyle->Red] Plot[x,{x, 0, 2}] Plot[x,{x, 0, 2},GridLinesStyle->Red] The style has not beenRead more