Many thousands of different kinds of laser are known, although most of these are not used beyond specialised research. The following is a list of common lasers, their operational wavelengths, and their applications.

{| border=1 cellspacing=0 cellpadding=4 ! Laser gain medium and type ! Operation wavelength(s) ! Pump source ! Applications and notes |- | Helium-neon (HeNe) gas laser | 632.8 nm (543.5 nm, 594 nm, 612 nm, 1.423 μm) | Electrical discharge | Interferometry, holography, spectroscopy, barcode scanning, alignment, optical demonstrations. |- | Argon ion gas laser | 488.0 nm, 514.5 nm, (351 nm, 465.8 nm, 472.7 nm, 528.7 nm) | Electrical discharge | Retinal phototherapy (for diabetes), lithography, pumping other lasers. |- | Carbon dioxide gas laser | 10.6 μm, (9.4 μm) | Transverse electrical discharge | Material processing (cutting, welding, etc.), surgery. |- | Excimer chemical lasers | 193 nm (ArF), 248 nm (KrF), 308 nm (XeCl), 353 nm (XeF) | Excimer recombination via electical discharge | Ultraviolet lithography for semiconductor manufacturing, laser surgery, LASIK. |- | Dye lasers | 390-435 nm (Stilbene), 460-515 nm (Coumarin 102), 570-640 nm (Rhodamine 6G), many others | Other laser, flashlamp | Research, spectroscopy, birthmark removal, isotope separation. The tuning range of the laser depends on the exact dye used. |- | Ruby solid-state laser | 694.3 nm | Flashlamp | Holography, tattoo removal. The first type of laser invented, in 1960. |- | Neodymium YAG (Nd:YAG) solid-state laser | 1.064 μm, (1.32 μm) | Flashlamp, laser diode | Material processing, rangefinding, laser target designation, surgery, research, pumping other lasers. One of the most common high power lasers. |- | Titanium sapphire (Ti:sapphire) solid-state laser | 660-1100 nm | Other laser | Spectroscopy, LIDAR, research. This high-tunable infrared laser is often modelocked to produce ultra-short pulses. |- | Holmium YAG (Ho:YAG) solid-state laser | 2.1 μm | Laser diode | Tissue ablation, kidney stone removal, dentistry. |- | Erbium doped fibre laser | 1.53-1.56 μm | Laser diode | Optical amplifier for telecommunications over optical fibre. |- | Semiconductor laser diode | wavelength depends on device material: 0.4 μm (GaN) or 0.63-1.55 μm (AlGaAs) or 3-20 μm (lead salt) | Electrical current | Telecommunications, holography, laser pointers, printing, pump sources for other lasers. The 780 nm AlGaAs laser diode, used in compact disc players, is the most common type of laser in the world. |}

See also laser construction.