A qualifier adds an extra "quality", such as specifying volatility or constness of a variable
They're similar to adjectives: "a fickle man", "a volatile int", "an incorruptible lady", "a const double". With or without a qualifier, the variable itself still occupies the same amount of memory, and each bit has the same interpretation or contribution to the state/value. Qualifiers just specify something about how it may be accessed or where it is stored
Credits goes to Tony_D @ What is the meaning of "qualifier"?
