A laser pointer is a small laser designed to highlight something of interest by projecting a small bright spot of coloured light onto it. Most laser pointers have low enough power that the projected beam presents a minimal hazard to eyes for incidental exposure. The laser beam is not in itself visible from the side, but is visible as a result of light scattered by dust particles along the beam path.

The small width of the beam and low power of typical laser pointers makes the beam itself invisible in a reasonably clean atmosphere, showing a point of light when striking an opaque surface. Some higher powered laser pointers are faintly visible via Rayleigh scattering when viewed from the side in moderately to dimly lit conditions. The early laser pointers were helium-neon (HeNe) gas lasers and generated laser radiation at 633 nanometer (nm), usually designed to produce a laser beam with an output power no greater than 1 milliwatt (mW).

The least expensive laser pointers use a deep red laser diode near the 670/650 nanometers (nm) wavelength. Slightly more expensive ones use a red-orange 635 nm diode, making them more easily visible than their 670 nm counterparts due to the greater sensitivity of the human eye at 635 nm. Other colors are possible too, with the 532 nm green laser being the most common alternative.

In the past few years, yellow-orange laser pointers, at 593.5 nm, have been made available. In September 2005, handheld blue laser pointers at 473 nm have also become available. Very recently, blu-ray/violet lasers at 405 nm have also become available.

The apparent brightness of a spot from a laser beam depends not only on the optical power of the laser and the reflectivity of the surface, but also on the chromatic response of the human eye. For the same optical power, the green laser will seem brighter than other colors because the human eye is most sensitive at low light levels in the green region of the spectrum (wavelength 520 - 570 nm). Sensitivity decreases for redder or bluer wavelengths.

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