A pen drive is a memory device.
A Flip-Flop (an electronic device) is treated as a memory element, which is capable of holding 1-bit (bit - Binary digit i.e., 1 & 0).
Group of 8-Flop-flops store 8-bit memory. 8-bit (1-Byte) memory can represent 256 data values.
A small flash memory chip contains millions of flip-flops.
A 1GB contains 1,00,00,00,000 Bytes in turn 8,00,00,00,000-Bits, it means 8000 Millions of Flip-flops embedded on a single chip.
You can apply this to 2GB, 4GB, 8GB, 32GB and so on.
"In a single sentence, a pen drive internal circuit contains group of interconnected flip-flops".
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