Methane is the most effective global warming greenhouse gas and methanogens are the key microbiota in methane emission. Emerging research focuses on ruminant methanogens due to their emission of methane globally; of which around 20% is from livestock. Enhanced techniques revealed the methangens diversity, adaptation in rumen, methanogenesis and their reduction strategies. Based on diet, geographical location, type of ruminant species, methanogen population shows vast diversity. Many strategies also interfere to reduce the methane emission worldwide such as dietary composition, vaccines, plant secondary metabolites, analogs and fungal secondary metabolites. This review gives a concise knowledge of methanogens' interference in methane emission and research and development techniques used for reducing methane emission.