There are many ways to print photos. For example you could download the photos to your computer choose the ones you like burn them on a CD and take them to a printing service. DPOF makes such photo printing easier here is how.
DPOF is a standard that was introduced by a consortium of camera and printer manufacturers. The goal of DPOF was the make photo printing easier and faster.
DPOF stands for Digital Print Order Format. The goal behind DPOF was to make the process of choosing which photos to print and printing them much easier and faster. If your camera supports DPOF then you can choose the photos you would like to print and the number of copies directly on your digital camera. This data is also known as the print order and is saved in the cameras memory card (the same memory card where photos are saved) in special files. Later on you can take the memory card with the photos and the DPOF data to any printing service that supports DPOF and it would automatically print the photos based on the DPOF print order data. Alternatively you could plug the memory card to a photo printer that supports DPOF and print all the photos that you chose with a single push of a button.
DPOF can do much more than just specify which photos to print and in how many copies. You can also specify additional information such as a photo title text, photo orientation, print paper size and more. Other useful information can be added: your contact information and your camera settings when taking the photo. All that information can make printing easier for example you can drop off a memory card with any printing service and they can know exactly which photos to print, in how many copies on what paper sizes and in what orientation. They also have your contact information where they can reach you when the prints are ready or if there is any problem.
Not all cameras support DPOF and the ones that do support DPOF vary in their level of support. For example the simplest support would be for choosing which photos to print and in how many copies while more advanced support would be for enabling other data such as title photo title text, paper size, contact information and more.
DPOF was extended to support more than photo printing. Examples of new features enabled by DPOF: you can choose photos to be emailed as file attachment. The usage is very similar to choosing which photos to print but instead of printing the photos when you plug your memory card to your computer special software reads the DPOF data and emails the photos you have selected to the designated email addresses. Another feature is slide show or photo projection: the photos you choose can be replayed as a slide show on a computer or be projected using a photo projector. For example you could plug the memory card to a projector that supports DPOF and with one click play the slide show of your choice.
Some PC software allows you to define any custom action to be executed on the DPOF data. For example the software can be told to copy all chosen photos to the hard disk and discard the others or to print all chosen photos, copy them to the hard disk and then create a backup of them on a CD this is a great way to automate some photo processes and can save time.
DPOF is not a must have feature but a good option if you want to save some time and make photo printing easier. Many cameras support DPOF but most users are not aware of it and are not using it. Check if your camera supports DPOF and learn how to use it to your benefit.