Deoxyribonucleic acid, or DNA as it's usually called...

https://www.sciencefocus.com/the-human-body/dna

DNA is the only molecule capable of reproducing itself. DNA is present in almost all living cells of all living things. Only DNA, and no other molecule, carries the ability to copy and then pass heritable information to subsequent generations. DNA is, indeed, the essence of life itself.

Despite these apparently magical tricks, DNA follows the ordinary laws of science and nature. Sometimes those rules are not obvious, but a little scientific digging and reliance on robust evidence will ferret them out.

What does DNA look like?
Physically, DNA is a chemical in the form of a twisted, extendable ladder, the iconic 'double helix'. The 'ladder' is composed of 'rungs' and sugar-phosphate 'siderails'.

The rungs consist of a pair of the small chemical bases: adenine, thymine, cytosine, and guanine, abbreviated A, T, C, and G, respectively Crucially, adenine (A) pairs only with thymine (T), and cytosine (C) only pairs with guanine (G). Only the pairs of either A:T or C:G fit as rungs between the two siderails.

The weight and structure of the DNA ladder naturally twists it into the double helix shape. And the ladder molecule can extend great distances [fashioned in continuance]. In a human cell, for example, the number of DNA bases pair rungs in the DNA runs over three billion, measuring over six feet in length.

However, in multicellular organisms like humans, the DNA does not remain as one long strand, but is cut and tightly packed into chromosomes.

Human DNA extracted as a single molecule from a single cell extends to just under two metres long, but is ordinarily segmented and stuffed into 23 pairs of chromosomes in each cell.

What does DNA do?
All bacteria, plants and animals, including humans, use DNA as the repository of their hereditary information. That is, the recipe to confer every genetic trait, from eye colour to blood type, is carried by segments of DNA stored within each cell of the organism. These DNA segments carrying genetic information are called genes, the root word of genetics.

What differs between human DNA and tomato DNA, or, for that matter, the DNA between two humans, is the precise sequence of DNA base pairs A, T, C, and G. By way of analogy, two different recipes in an English language cookbook may use the same 26 letters to make words but differ in the exact sequence of those same 26 letters, resulting in different recipes.

Although DNA is physically the same ‘double helix’ composed of long segments of A:T and C:G base pairs in all living things, the exact sequence of those bases varies from one organism to another. It is the order of bases that provides the instructions to produce, say, insulin in human pancreatic cells or photosynthetic enzymes in plants. A plant’s DNA lacks the base sequences instructions to make insulin, and human DNA lacks instructions for photosynthetic enzymes.

In any organism, such as a given human, the DNA in every cell has the same base sequence as every other living cell in that human.

The difference between a liver cell, and a skin cell is that while both activate ('express') those genes required for basic living processes, the liver cell expresses those genes for liver proteins. Other genes remain present, but are not expressed. Meanwhile, skin cells express the genes unique to skin proteins, but liver (and other) genes are silenced.

Does every living thing have DNA?
The language of genetics is the same in all of life. A gene from any cell of any living thing can be copied, transferred and understood by any other living thing to make the same protein.

For example, human insulin is now made by microbes genetically engineered with the human DNA recipe for human insulin. That is, a copy of the human insulin gene is transferred to microbes, and those microbes read the human insulin gene recipe and make insulin, even though the microbes — having no blood or blood sugar — have no use for insulin. Similarly, most hard cheeses now are made with chymosin (a milk clotting enzyme) generated by genetically modified microbes.

A more interesting question, scientifically, is “Did life arise more than once?”

Answer: unlikely. The evidence is based on DNA being the sole common feature of all living things. More importantly, the language DNA uses to convey information is common to all; the same language is read and understood by all living things. And most importantly, the DNA language is not just the common language used by all species; it is the only language used by any species.

There are no other languages of genetics.

When considering the number of potential languages DNA might have used instead, the fact that all known life forms use the same language of DNA to communicate the same information is compelling evidence that life arose only once.

By now all of us are experts on DNA, what it means and how it works

And how the ladder molecule of DNA can extend great distances

Daniel 12:1
King James Version
12 And at that time shall Michael stand up, the great prince which standeth for the children of thy people: and there shall be a time of trouble, such as never was since there was a nation even to that same time: and at that time thy people shall be delivered, every one that shall be found written in the book.

Psalm 139:16
Thine eyes did see my substance, yet being unperfect; and in thy book all my members were written, which in continuance were fashioned, when as yet there was none of them.

You see this book that is in reference, it is your DNA. Your genome. All your members are written in this book; your heart, your kidneys, your liver, your spleen, your brain, your pancreas, your limbs, your eyes, your ears, your teeth, everything that composes you is written in your DNA. The miracle of medicine is that any part of your body that has become defective can easily be replaced. For example, it is just to Identify the sequence that codes for any body part and use it to build a new spare in the lad and replace the failing one with a brand new.
The covid vaccines were DNA altering vaccines. You are no longer as written in the book because you have been genetically altered if you received the covid 19 vaccines

https://www.cshl.edu/the-complete-human-genome-a-book-of-life/
The human genome has been referred to as the “book of life,” containing all the necessary instructions to build a human being.

That’s why an international team of researchers set out to figure out what the working parts of the human genome are, and what they mean for the human body as we know it.

https://edition.cnn.com/2012/09/05/health/encode-human-genome/index.html
The project is called the Encyclopedia of DNA Elements (ENCODE). When the Human Genome Project sequenced the human genome in 2003, it established the order of the 3 billion letters in the genome, which can be thought of as “the book of life.”

Adenine, Guanine, Thymine, and Cytosine are the four bases of DNA. In RNA the Thymine is replaced by Uracil. DNA is a double strand helix structure while the RNA is a single strand

DNA is Deoxyribonucleic Acid
RNA is Ribonucleic Acid

The DNA forms the building blocks of specific proteins and these proteins are the ones that are configured together to form the various body parts. The DNA of everyman is unique, even among identical twins.

The DNA sequence is a very long ladder like structure and there are segments within the ladder, and each segment codes for different kinds of amino acids, and the configuration of different amino acids gives rise to different kinds of proteins and different kinds of proteins give rise to different kinds of tissue, and then different kinds of tissues make up individual organs, and organs functioning together give rise to systens, and the systems cooperating and complementing each other gives rise to the organism

Psalm 139:14-16
King James Version
14 I will praise thee; for I am fearfully and wonderfully made: marvellous are thy works; and that my soul knoweth right well.

15 My substance was not hid from thee, when I was made in secret, and curiously wrought in the lowest parts of the earth.

16 Thine eyes did see my substance, yet being unperfect; and in thy book all my members were written, which in continuance were fashioned, when as yet there was none of them.

So, the DNA is like a book, like a manual, wherein all your members are written, members/organs, it is like the primordial soup from which everything fits together to form a whole functioning organism.

The DNA is the book of your life

A single cell that contains billions of instructions, far more complex than even the most supercomputer we have today and packed in a space of 20-30nm is considered a work of random event while a supercomputer chips that is less complex and packed in 16X16mm silicon wafer are considered to be a work of genius and intelligent designer.

God is truly wonderful!