The discovery of DNA by Watson and Crick led to the idea of Central Dogma, stating that the genetic information stored in DNA is transcribed to mRNA to produce protein. The idea is that the gene or DNA is directly responsible for the coding of proteins in the organism. But that constitutes only 1% of DNA and the remaining 99% are non-coding. Coding RNA (mRNA) encodes protein while non-coding RNAs have no protein-coding capacity. With the development of Next Generation Sequencing Technology large numberof non-coding RNAs have been discovered. Again, Transcriptome analysis in mammals and many organisms showed that there is large number of long transcripts having no protein coding capacity are known as Long Non-coding RNAs or lncRNAs. The function of lncRNAs that regulate mainly gene expression has been discussed. The role of lncRNA in Abiotic and Biotic stresses of plants has been shown. Then the role of lncRNAs in human diseases like neurodegenerative disease and cancer has been discussed with their therapeutic and diagnostic uses.