Mathematica

Plotting

Tick marks and GridLines

Plot[3 Sin[x], {x, -2 Pi, 2 Pi}, 
 Ticks -> {{-2 Pi, -3 Pi/2, -Pi, -Pi/2, Pi, Pi/2, 3 Pi/2, 2 Pi}, 
   Automatic}, 
 GridLines -> {{-2 Pi, -3 Pi/2, -Pi, -Pi/2, Pi, Pi/2, 3 Pi/2, 2 Pi}, 
   Automatic}]