DNA and RNA are totally different. DNA, stands for Deoxyribo Nucleic Acid, is a long polymer with a deoxyribose and phosphate backbone and four different bases: adenine, guanine, cytosine and thymine (A,G,C,T), while RNA,stands for Ribo Nucleic Acid, is a polymer with a ribose and phosphate backbone and four different bases: adenine, guanine, cytosine and uracil (A,G,C,U). DNA can only be found in nucleus, while RNA can either be found in cytoplasm or nucleus. Generally DNA is a double-stranded molecule with a long chain of nucleotides, while RNA is a single-stranded molecule with a short chain of nucleotides. DNA is a medium of long-term storage and is used in transmission of genetic information. RNA is not. Its job is to transfer the genetic code needed for the creation of proteins from the nucleus to the ribosome. To make protein, mRNA must first be sythesized from a DNA template. This step is called transcription. Then ribosomes will synthesize proteins using the mRNA transcript produced during the transcription process. By the way, mRNA is just one type of RNA, which stands for Messenger RNA, while the other two types of RNA are rRNA (Ribosomal RNA) and tRNA (Transfer RNA).