LOL. Yes it always depends on what 'it' is being referred to.
And yes what people hear and repeat is could either be comletely erroneous, or something that changed over time. We can just look in the various service manuals etc and see that thermostats were changed, cap pressures changed, overflow recovery tanks added. What was done on an 'open' system without emissions idle settings was different that recovery systems later in the emissions era. blah blah yada yada