These new generation fluorescent materials may now challenge the domination by inorganic semiconductor materials of the commercial market in light-emitting devices such as light emitting diodes (LED) and polymer laser devices. This review provides information on unique properties of LEDs and how they have been optimized to generate these properties. The review is organized in three sections focusing on the major advances in light emitting materials, OLEDs, polymer light emitting diodes and understanding the desirable properties as well as modern solid state lighting and displays. it is clear to motivate these organic light-emitting devices (OLEDs) and organic lasers for modern lighting in terms of energy saving ability. In addition, future aspects of conjugated polymers in LEDs were also highlighted in this review.