Photoshop – Understanding Layers
One way to understand layers in Photoshop is to imagine you have thin sheets of transparent glass, it is our layers. In this example, say three layers. One of these layers will be your background. The bottom layer remains in place. All the layers are stacked on the bottom layer so you can see the background image. Your background layer is an image of a rose. You can superimpose an image of a hummingbird on the image of the rose, making it appear that the hummingbird hovers above the rose. Layers with each other through the cover (opacity refers to the degree of transparency is a layer). By adjusting the settings, you can cover your background layer partially show through the top layer. The more you set the opacity to 0% to set the top layer is transparent, allowing more of the base coat to show through.
You can also change the stacking order in the Layers panel. You can use any layer on and off by clicking the eye beside the layer you are working. So if we wanted to see what the image would look like without the rain, simply click the eye icon beside the layer to the image of the rain turning the layer off, making the layer invisible.
Keeping the window is visible, you can see which layer you are working only by a look and see which layer is highlighted.
I now have the possibility of all the layers into one, so I finished all operations on separate layers into one layer.