Digital Research
When you compare the technology and power of a personal computer today relative to even the supercomputers of only a decade or so ago, even commercial business systems of the past. Today people and business use computers for all osrts of things, and today we can use the internet to find info about anyone with a reverse phone lookup, a pc and a website can give you a full background check on anyone you know. The modern pc is such a useful piece of equipment these days especially combined with the internet connection which most people these days have. You can do in depth research for free, you can access the sort of info that in the past was restricted to private investigations, and access scientific and technical papers previously restricted to large scientific libraries.