All digital cameras that I know are using a cryptic naming convention for images taken with them. When you copy the pictures from the digital camera to your computer you will have a bunch of files on your hard drive like CIMG0001.jpg, CIMG0002.jpg and so on and it's quite hard to find out where and when the image was taken and what is shown on it.
The CIMG files are created by my Casio Exilim EX-Z700 digital camera and other cameras uses other naming conventions. They all do have those cryptic names in common though. It takes a long time to rename the pictures manually and that is why programs like Nameexif will become increasingly popular.
Nameexif is a software to batch rename pictures taken with your digital camera. Several possible output names can be chosen. The new filenames always start with the date and time to preserve the chronological order of the pictures. Two optional parameters can be chosen, those are to add the original filename to the end or add a custom name to the new filenames.