Wow! They weren't even caching database calls: HealthCare.gov had been constructed so that every time a user had to get information from the website's vast database, the website had to make what's called a query into that database. Well-constructed, high-volume sites, especially e-commerce sites, will instead store or assemble the most frequently accessed information in a layer above the entire database, called a cac…
Depends on what industry you work in. A Cache may look more like a giant pile of weapons as opposed to some memory in a computer.