Non-coding RNA (ncRNA) are functional RNA molecules that are not translated into proteins. ncRNA can be classified into long ncRNAs (lncRNAs) and Small ncRNAs. Small ncRNAs include many different RNAs, such as microRNAs (miRNAs), small nucleolar RNAs (snoRNAs), transfer RNA (tRNA), piwi-interacting RNAs (piRNAs) and small interfering RNA (siRNA). lncRNAs are the most ubiquitous and functionally diverse class, they include linear lncRNAs and circular RNAs (circRNAs).