In Photoshop you can use the blend modes to change how layers interact with each other, thus producing interesting artwork. Think of each layer as a transparent glass canvas, what is placed on the top ...
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Layer Masks in Photoshop explained

Masking is the secret weapon behind many jaw-dropping designs, making it one of the most powerful techniques you can master ...
If you’re editing a product photo, creating a realistic drawing, or simply want to add depth to an object, consider applying a shadow effect. There are two easy ways to add shadow in Adobe Photoshop ...