This is not to criticize some "mixed terminology" being used; it is of no
consequence in this thread but it is of interest in its own right:
People often use and confuse "digitizing", "sampling", and like terms. A
"sample and hold" circuit grabs a changing analog voltage and holds its
instantaneous, current value (e.g.. on a capacitor). This is a "sampling"
operation and the result is an analog voltage. An ADC might then
represent that analog voltage by a series of several binary (or other
base) digits. Perhaps the most visible difference is that the sampled
analog voltage exists as the potential of a single wire or terminal; its
digital counterpart is carried on several wires, or terminals, one for
each digit.
There are many consumer applications of sampling, recording and re-playing
signals - all in the analog domain. Talking greeting cards and toys
abound with this "analog memory" technology. Non-volatile analog memory
chips are (or used to be) available at Radio Shack - quite cheap. I think
RS catalogued them as "digital memory chips" in unison with the common
confusing of "sampling" with "digitizing".