Photoshop layers follow a concept similar to that of stacked sheets of acetate. Therefore, each layer contains unique graphic elements, that can be seen even with other layers on top of them, as long as they occupy transparent areas. The layers can be rearranged and placed on top of each other. Depending on the objects they contain, they should be placed in the upper part of the layered area, giving them priority display, or in the lower part, being hidden or semi-hidden.

Various tasks can be performed within a layer, such as compositing several images, adding text, or adding a vector shape. Layers are also an ideal system for applying effects to specific objects, without affecting the rest of the elements of the project.

Another recurring purpose of layers is to edit without destroying the original. Thanks to them, you can apply filters or effects to images without having to type the changes. If you are not satisfied with the result, just delete the layer and any modification will disappear.

To improve navigation within the project, layers can be renamed and grouped. It is also possible to temporarily disable them to see the content below them. They even have an opacity control, which makes their content fully or partially transparent.

Depending on the performance of your computer, Photoshop will be able to open a greater or lesser number of layers. Each layer increases the pressure this editing application puts on the processor and decreases the free RAM space. Therefore, the more layers a project has, the more resources your computer must use.