I added some more to the post above.
I assume you're asking about the ATV grid sampling from the picture on the website. Inside that box is just an old laptop hooked up to the GPS receiver on the right. I can't remember what program we use but it's just software to grid out a field. We usually run the perimeter of the field then the program will grid out 1.6ac (this is what we use the most but I have done 1 ac and 2.5 ac) blocks and we take a sample at the center of each box. The sample is small bag, about 10 cores, 6 inches in depth. Those samples are sent in for analysis and we get a fancy report back that details specific conditions of each grid. We have a couple machines, the precision ag ones, that then use those analysis to automatically change type and rate of fertilizer we apply to the field.