This review discusses the roles, functions, and mechanisms of long non-coding RNAs (lncRNAs) in cancer. LncRNAs, which are RNA molecules longer than 200 nucleotides, play significant roles in chromatin remodeling, transcriptional and post-transcriptional regulation, and cross-talk with other RNA species. They can function as decoys, scaffolds, and enhancer RNAs. The review highlights the characteristics of lncRNAs, including their low expression levels, diverse functions, and involvement in various cancers. It also describes methods for identifying and annotating lncRNAs, such as RNA-seq, custom microarrays, and various sequencing techniques. The review further discusses the potential of lncRNAs in therapeutic applications, particularly through antisense oligonucleotides (ASOs), and explores future research directions, including the discovery of novel lncRNA mechanisms and the development of personalized therapies.This review discusses the roles, functions, and mechanisms of long non-coding RNAs (lncRNAs) in cancer. LncRNAs, which are RNA molecules longer than 200 nucleotides, play significant roles in chromatin remodeling, transcriptional and post-transcriptional regulation, and cross-talk with other RNA species. They can function as decoys, scaffolds, and enhancer RNAs. The review highlights the characteristics of lncRNAs, including their low expression levels, diverse functions, and involvement in various cancers. It also describes methods for identifying and annotating lncRNAs, such as RNA-seq, custom microarrays, and various sequencing techniques. The review further discusses the potential of lncRNAs in therapeutic applications, particularly through antisense oligonucleotides (ASOs), and explores future research directions, including the discovery of novel lncRNA mechanisms and the development of personalized therapies.