Watermark
Watermark
A mark or technique added to images, videos, and other digital content to identify its creator or copyright owner.
In Simple Terms
A watermark is a faint name or logo added to the corner or edge of an image or video. You've probably seen sample images online with large diagonal text stamped across them. It's there to discourage unauthorized use and to show who created the work.
Behind the Name
The term "watermark" comes from traditional papermaking. While paper is still wet, a mold alters its thickness and density to create a faint pattern — one that resembles a mark left by water, giving the technique its name. Today, the same idea applies to digital data: overlaying a subtle logo or mark onto images and videos serves the same purpose.
Take a Closer Look!
A watermark is a mark added to digital images, video, or audio to link the content to its creator or rights holder.
There are two main approaches: a "visible" type that overlays a logo or text onto the content, and an "invisible" type that embeds a signal within the data itself in a way that's barely noticeable.
The visible type is created by layering a logo or text over the original content, so the overlap shows up directly in what you see. It instantly signals who made the work, and having a prominent logo in the way can also discourage unauthorized use.
The invisible type works by making tiny changes to the data itself — such as color values or frequency components — that are nearly impossible to detect by eye or ear. Since it isn't meant to be seen or heard, the information can only be extracted using specialized analysis tools.
Both types, though, have a second use. If everyone gets the same mark — a rights holder's name or logo — it only identifies the creator or discourages unauthorized use. But embed a different name or ID for each recipient or file, and a leaked copy can be traced back to whoever it was given to: a visible mark might show a faint recipient name in the corner, while an invisible one embeds an identifier only a specialized tool can read. Either way, traceability comes from giving each copy a unique identifier — not from whether the mark itself is visible. Put simply, it's like an "author's signature" written directly into the data.