Laser beams can be modulated just like radio and microwave beams can.
Likewise, laser beams can be encoded with communications signals such as voice and data signals. Most modern-day Internet connectivity is accomplished via laser beams travelling through fiber optic cable. Free-space optical communications, often referred to as FSO, can also be accomplished with beams transmitting through the open air or even space.

Figure below shows a typical FSO laser transceiver. The device has multiple laser transmitters with small optical apertures in comparison to the larger receiver aperture in the middle. There is also an alignment monocular that aids the operator in pointing the system at the partner FSO transceiver station.

Figure below shows how laser beams are used terrestrially as well as spaceto-space, space-to-ground, and ground-to-space to transmit data. Optical links are inherently more secure and free of “eavesdropping” than typical radio or microwave communications because they are point-to-point over a tight beam. Since they are optical beams clouds, smoke, rain, snow, and other optical path obscurants do cause a reduction or loss in data transmission.