From all we know about the Universe, something like 96% of its total matter-energy component is missing! All we see and detect directly in the Universe, the familiar baryon matter, atoms, accounts for only about 4% weight of the Universe. Dark matter and dark energy, together, the dark side of the universe are invisible to our telescopes and they dominate over the dynamic of the cosmos and its structure and still we do know what they are. In my talk I review the current status of cosmology and how we try to understand these mysterious components of our Universe. The talk would be understandable for general public and under-graduate students.