difference between traditional incandescent light bulbs and LED lights

The essential difference between traditional incandescent light bulbs and LED lights is that the former wastes up to 98% of the electricity supplied as heat but does shine light in all directions, whereas LED light sources convert nearly all their electricity into light (hence the reason they stay cool to the touch) but shine a pure and very intense directional light.

The other key differentiator is cost of ownership. LED light bulbs last an incredibly long time (3+ decades of normal use) and cost so little to run that the cost of the electricity used throughout the entire lifetime of a bulb is almost certain to be less than the cost of the bulb itself. This is in stark contrast to normal non-LED bulbs that are typically well over 500 times the price of the bulb itself in running and replacement costs.

These particular qualities (highly efficient, zero fire risk and focused light) make LED light bulbs a perfect replacement for spot lights, especially the ubiquitous halogen lamps now found in many homes and that waste heat and money in abundance.