Desktop search?

Can someone explain in laymans terms what desktop search will actualy do for me?

I know I can search for files with windows already, I can also open up folders on my C drive and find programs and stuff. What’s all is desktop search supposed to DO that is supposed to be revolutionary.

Picture this: your wife types in “whipcream” to find the recipe for applepie that she has seen on the internet recently (and is still sitting in a cached webpage). So Google finds the page, but also the chat log to your secret love in which you confess the desire to engage in kinky sex with her.

Does this make things clearer?