so, the main thing is obviously
Windows Solitaire pedantically speakin', what Windows calls Solitaire is more correctly named
Klondike -- "Solitaire" is no specific game at all, it's an umbrella term meaning
any kind of table-top game that you play by yourself Solitaire was made a standard component in 1990 as kind of a tutorial/demo,
"to soothe people intimidated by the operating system", in particular by familiarizing them with the exotic practice of
drag & dropSolitaire is also well known as the classic method, pre-ubiquitous-Internet, for bored office workers to avoid working
the card deck rendering system was actually not part of Solitaire itself, but a shared system file called
CARDS.DLLthere were even
tutorials made about how to use this DLL to render your own card games(however, CARDS.DLL has not been a part of Windows since Vista, when Solitaire's graphics were modernized for a discerning 2006 audience...)
CARDS.DLL deck art by Susan Kare