Detective Pux here, ready to explain the world of photo printing.

First off, let's talk about photo print sizes. In the USA and Europe, the most common sizes are 4x6, 5x7, and 8x10 inches. 

When it comes to photo print sizes, there can be some variations between the US and Europe. In the US, some of the most common print sizes include 4x6, 5x7, and 8x10 inches. In Europe, however, photo print sizes are often measured in centimeters rather than inches, so you may see sizes like 10x15 cm, 13x18 cm, and 20x30 cm.

But why stop at just those sizes? With the advancements in technology, you can now print your photos in all sorts of fun and unique sizes. Want a giant poster size print of your favorite vacation photo? No problem! How about a tiny little print to put in a locket or charm bracelet? Easy peasy. The world is your oyster when it comes to photo print sizes.

Now, onto the question of why inkjet photo prints often lose their color over time. Well, my dear readers, it's all in the ink. Inkjet prints rely on ink being absorbed into the paper, but over time that ink can start to fade or shift. This is especially true if the prints are exposed to light or heat, which can cause the colors to fade faster.

But don't despair! There are ways to prevent this color fading. One solution is to use high-quality, archival grade papers and inks. These materials are designed to resist fading and last longer. Another solution is to store your prints properly, such as in a photo album or frame with UV-protective glass. And of course, if you want your photos to last a lifetime, consider making digital copies of them and storing them on a hard drive or the cloud.

In conclusion, the world of photo printing is vast and varied, with endless options for sizes and materials. And while color fading may be a concern, there are solutions to ensure your memories stay vibrant for years to come. So go forth and print those photos, my friends! And don't forget to have some fun with it.