Recent progress in producing, purifying, and delivering RNA to cells has paved the way for the creation of RNA-based treatments across a wide range of uses. These RNA-based drugs represent a quickly growing sector of medicine poised to revolutionize treatment standards for numerous conditions and bring personalized healthcare to fruition. These therapies are economical, relatively straightforward to produce, and capable of targeting pathways that were previously considered untreatable. This innovative therapeutic approach allows both small biotechnological firms and academic researchers to swiftly create novel and customized RNA molecules. In this chapter, we delve into the essential principles underlying several categories of RNA-based therapies. We cover a range of treatments, including antisense oligonucleotides (ASOs), which are designed to interfere with gene expression at the RNA level; aptamers, short RNA or DNA molecules with unique 3-dimentional structure that can bind to specific target molecules; small interfering RNAs (siRNAs), which play a role in the RNA interference pathway to regulate gene expression; microRNAs (miRNAs) which is involved in gene regulation and expression at the post-transcriptional level; and messenger RNA (mRNA), which is used for replacement therapy for loss-of-function diseases. Additionally, we present a historical summary of RNA-based treatments currently in clinical use. We also examine the benefits and challenges of RNA-based medications as well as different strategies for delivering RNA.