Do i need a tin foil hat?

I had a strange thing happen on my site, it was just a bit weird really. I uploaded a few images I wanted to try out as covers for my site using the Artificer style function. It worked great on images called red_robot_background or yellow_banana_background, but then I uploaded one I called blackwhite_robot_background. Basically the file names identify the image. It's just easier for my to upload quickly. Anyway, the images and all the same size, with, pixels ect except the image is different. Now the strange thing, all the images showed up on my site as covers except the image called 'blackwhite_robot_background'. I went all about the houses trying to see if i copied the path wrong, nope, corrupted the file, nope. Then I change the file name to robot_background and left off the 'blackwhite' and lo behold it worked. so i changed the name back as a test and again and the image didn't show. What the heck is all this about? Do i need a tinfoil hat here or is there some kind of sensor technology that inhibits what you call the files and what you can see? I mean mine was totally descriptive and I used the image in the header for this discussion to show this, it's just black and white. So are we as a society actually banning the words black white now or do I need a tin foil hat :)

inquiring minds need to know!