If your vehicle has power windows, the switches on the driver's door armrest control both windows.
In addition, the passenger's door has a window switch that controls that window. Press the front of the switch to open the window. Pull the switch up to close it.
The driver's window has an express-down feature which allows the window to be lowered fully without pressing and holding the switch. Press the front of the switch to the first position, and the window will open a small amount. Press the switch down fully and the window will go all the way down.
To stop the window while it is lowering, pull the front of the switch up.