Deoxyribonucleic acid or DNA – the chemical that stores genetic instructions in almost all known organisms – has an impressive data capacity. One gram can store up to 455bn gigabytes: the contents of more than 100bn DVDs, making it the ultimate in compact storage media.
To be clear, the researchers didn’t use living DNA for the tests. They say there would be too much room for error. Similar to the zeros and ones that power current technology, DNA uses the letters A, C, G, and T. The Guardian reports:
The fragments on the chip can later be "read" using standard techniques of the sort used to decipher the sequence of ancient DNA found in archeological material. A computer can then reassemble the original file in the right order using the address codes.