To store image parts.
Adobe Photoshop :)save images with layers in .psd format :)
There are many resources and websites that offer information about Photoshop layers. Some of these websites that offer information are Adobe, Photoshop Essentials and Photoshop Cafe.
Photoshop layers may not import into After Effects if the file format is not compatible or if the layers are not properly organized in Photoshop. Make sure to save the Photoshop file in a format that After Effects supports, such as PSD or TIFF, and ensure that the layers are named and organized correctly for easy import.
color layers is simply color layers
Open the Layers window.
There isn't default keyboard shortcut to link layers but you can assign shortcut from Edit > Keyboard Shortcuts.
Yes, .psd files maintain the layers you create in Photoshop so that the next time you open your .psd file in Photoshop you can continue to work directly onto the layers.
Use Transparency slider in LAYERS palette.
One layer.
There is no such option in Photoshop. If you mean Vector Photoshop shapes then the shapes can be used for infinite things in Photoshop such as layers, masks, as frames, as a source for selections, as a source for actual brushes, for patterns, for exporting to other applications, used in shape blurs, used as cookie cutters in Photoshop elements. Illustrator vector brushes exist as do expression and Xara vector brushes and many others but sadly, as yet, Photoshop has no vector format brushes.
To select all layers in photoshop for a PC open up your layers window (It is under window - layers), hold down the shift key and click on each layer that you want to group together or edit.
The factors that determine the sizes of Photoshop files include the resolution of the image, the number of layers, the complexity of the design, and the file format used for saving the image.