What is metadata?
Metadata is an information that describes, explains, locates, or otherwise makes it easier to retrieve, use, or manage an information resource. Metadata is often called data about data or information about information. When it comes to digital images, it is compared with the blank back of a printed photo. This is a place to write information about the image – who made it, who owns the copyrights, what is on the image, who is in the image, where it was made, when it was made and camera settings used to create it.
There are several ways to store metadata. And Dreamstime upload system supports automated EXIF/IPTC data retrieval.
So it's really handy to use some software, to store EXIF or IPTC data into an image file. This information can include your name, image title, description and keywords. And it will be always with the image, werever you want to use it.
There are some great pages about metadata, with lot of information and links:
www.iptc.org - software list