The creator of any work---whether it be a picture, painting, drawing, music or sculpture---is the considered to be the copyright owner. A watermark is a translucent notification that is placed on photographs indicating the work is copyrighted. It is a good idea to place a watermark on your photos if you are uploading them to a website where someone may download them without your permission. You can apply a watermark for free using a photo editing program.
Download a free trial of Adobe Photoshop or the free photo editing programs such as GIMP or Paint.net.
Open the program you just downloaded and open the photograph to which you want to attach the watermark. Although the wording will be slightly different from program to program, the steps are similar for each. GIMP and Paint.net are very similar to Adobe Photoshop in design, tool placement and wording.
Click "Layer" in the navigation bar of the program, and select "New layer."
Select "Overlay" and set the "Opacity" to 50 percent. A new layer will be created.
Click the "T" for the text tool; this will let you type in your notification. Change the font size to "48 pt," which will make the text large enough to be seen on the picture.
Type the words "Copyrighted Image" and press the enter button. You can reposition the notification by clicking and holding the mouse cursor on the word and move it to the location on the picture.
Click "Layer" in the navigation bar and select "Flatten image." This will allow you to save the picture with the notification now typed into it. Save the picture as a separate file so you do not change the original image.