/o/ stand for Auto- as you can tell just by the name, it's about cars. New cars, old cars, car designs, car fuck-ups, you got them all. Being one to laugh at the misfortune of others, I especially like the last one. For instance, here's a picture of what happens when you don't notice a large section of wire fencing being slowly wrapped around your drive shaft as you move along.
/f/ stands for flash. No, not the superhero, but the app. If you're on your Ipad right now, you're probably screwed for this part. However If you don't buy shitty Apple products, this will be entertaining. Since files on 4chan usually get deleted after a couple hours or so, and I don't know how to download an .swf, I won't post one. However, you can always go through and look whats up at the time. I have posted several of them before, to great success and hilarity. If you want to do so yourself, get the code from here. Then simply replace "2bigpinkballs2.swf" in both spots with the link to another one anywhere on the internet. You may also have to change the width and height to suit your page as well. Happy Trolling!