"May I use your camera, Dad?" There, I'd asked! Now, the wait, nervously wondering how he was going to respond. "Sure, but you've got to promise to ... well, I know you'll take care of it. Go get it from the desk and I'll show you how to handle it."
I must now admit to being pleasantly surprised, since at the time I'd figured there was little chance he would allow me use of his precious jewel-like German camera. Truth be told, back then I wasn't as good at putting machines back together as I was at taking them apart to see how they worked! Nevertheless, my pockets stuffed with several little metal cans containing rolls of outdated Agfa film he had scrounged up for me, I ended up leaving the house with the camera, my first attempt to "capture the light" ...
... and, yes, it was quite some time before I began to understand the relationship between f-stop, shutter speed, and ASA. After that came focus, depth of field and circle of confusion, the Zone System, exposure latitude, reciprocity failure, and the fundamental "rule of thirds." Now ... well, I'm still learning!
What happens when I take pictures? I'm not sure. Closest description of my feelings that I've ever heard was my friend Carl, who said, "Pat, you see things that most of us merely look at ... you stop and notice what most of us pass by." Whatever it is, I'm always pleased to think there are others who enjoy sharing my vision.