Watermarking is a technique used to embed a visible or invisible mark onto digital content, such as images or documents, to protect against unauthorized use or copyright infringement.

Visible watermarks are typically translucent text or logos overlaid on the content, while invisible watermarks are embedded within the data itself. Both types serve as a deterrent and provide a means of identifying the original creator.

Watermarking can be achieved using various algorithms and techniques, including digital signatures, steganography, and spatial domain methods. It is widely used in industries like photography, publishing, and digital media to safeguard intellectual property and ensure content integrity.