[Fathom Zero]

Basically, (and I mean basically), a box is strapped to the back of your TV and your cable or sattelite or whatever is routed through it and the information about what you or your family have watched and at what times is recorded and sent back to ACNielsen who compiles it and adds to together with everyone else's viewing numbers and the information is made available to everybody. (and and and and and)

It's how most of the networks schedule their programmings. I.E. it would be better to schedule a show that appeals to a lot of people at the prime time-slot. Hence "primetime', the time from when people start eating dinner together to before they go to sleep. Advertising is more expensive in such slots.

The box I'm getting scans my family's buying trends. Say we only get food that is yellow. Well, when Nabisco or whoever sees that we and many other families only buy yellow food, they're not gonna put out green things. They're gonna make sure that we buy their products the most by catering strictly to the numbers. That's an exageration, though.

That's the gist of it. I may not know everything about how it works, but I know it's incredibly important.