When you upload any of your own pictures that will be available to the public on your website/blog, it is a good idea to label a digital watermark on your image to ensure that the picture owned by you and it is not misused in any illegal way.
If you have some Photoshop skills, you can easily achieve to do so by using Adobe Photoshop software. Here is a free service that you can use to label your pictures without requiring any Photoshop skills!
A website known as PicMarkr lets you to add your choice of custom watermark by choosing how to place watermark at your own either image or text to your pictures online. This free tool is useful especially for you to add comments onto your photos and also when you need to protect your copyrights picture, you can label it with just few clicks.