* Messenger RNA (mRNA): This is the intermediary between DNA and protein synthesis. It carries the genetic code from DNA in the nucleus to the ribosomes in the cytoplasm, where proteins are made.

* Transfer RNA (tRNA): This molecule acts as a "translator" during protein synthesis. It brings amino acids to the ribosomes, matching them to the codons on the mRNA, building the protein chain.

* Ribosomal RNA (rRNA): This type of RNA is a structural component of ribosomes. It helps form the ribosome's structure and plays a crucial role in the catalytic activity of protein synthesis.

There are also other types of RNA, such as small nuclear RNA (snRNA) and small nucleolar RNA (snoRNA), which play important roles in various cellular processes, but the three main ones are mRNA, tRNA, and rRNA.