If we consider nucleotides A, T, G and C as elements of description and storage of data, analogs of 0 and 1 in the binary system of calculus, then it becomes possible to encode some information with their help. And write it down, keeping it in the DNA molecule, which consists of adenine, thymine, guanine and cytosine. This is exactly what the scientists from the Swiss ETH Zurich did.
The Swiss chose for the experiment the musical album "Mezzanine" by Massive Attack, one of the most popular albums of 1998. But this is only 15 MB of data, and the largest amount of information recorded on DNA is 200 MB. It was created at Microsoft, having recorded one of the videos of the famous music group OK Go!
To write an informational DNA molecule, you must initially translate the binary code into a quaternary one, but with restrictions on possible bonds between nucleotides. Further, the DNA molecule itself is synthesized by the code, and this is an extremely long and laborious process. It cannot be compared with recording on silicon-based media; at the current stage, the technology is not suitable for mass use in principle.
And what, then, is its advantage? First, the enormous capacity of the carrier - 1 gram of DNA molecules can store a billion terabytes of information. Secondly, any physical medium degrades and wears out from time to time. DNA is used to create countless copies of itself from new materials, and therefore a priori "eternal". In a dehydrated state, a molecule can be stored for tens of thousands of years, and if you use genetic engineering, then any flower or mold can be turned into a "copy center", where the data once recorded on DNA will be reproduced in a natural way.