Genetics and deoxyribonucleic acid, better known as DNA, are not exactly the same, but they are linked. In DNA, there are four types of encoded molecular information. These are called nucleotides. In the long chains of spiralling DNA that exist in all living things – including people, of course – these nucleotides can be arranged in many different ways. Depending on the sequence of these arrangements, different genetic codes can be written into them. As such, you can think of genes as individual letters but DNA as words, sentences and even paragraphs of information. Though one would not exist without the other, they cannot be described as the same thing.