saving data from arduino to a flash memory about for example 8G

i want save the real time data from a sensor into a flash memory. my arduino is uno. i need to save the data from a sensor which is run by arduino uno. is it applicable? if yes, which modules are needed? thank you.

Do you mean to save data to a SD card?

Or eeprom? Saving data to flash (code memory) is not possible without tricks.

How much data are we talking about? One measurement every second, every hour or ...