From the time you were very little until you became an adult, you understood that people were motivated to "couple." Moms coupled with Dads, Grandmas with Grandpas, and Aunts with Uncles were all coupled together. It was not long before you figured out that other things coupled too. In fact, things that coupled did so because of objects known as "couplers." Couplers connected objects together, and couplers help objects stay together. These objects have a sort of relationship with each other, which is an interesting view to investigate between the following objects.

Radio Transmitters/Receivers and Antennas 

Radio transmitters/receivers are coupled with antennas through the use of antenna couplers. Without the antenna couplers, antennas would never attach to radio transmitters or receivers. If antennas never coupled with transmitters or receivers, you would never have car radios, broadcasting stations, or CB radios inside semi-trucks and police cars. When these objects are coupled, they connect to the world, and the world is able to communicate with everyone in it. That is some relationship those antenna couplers form.

Output Couplers and Lasers

In an industrial setting where lasers are used, you need output couplers. These couplers "couple" with the lasers by allowing the laser beams to connect to their mirrored surfaces, and then bouncing those reflected laser beams onto other surfaces. The beams may be used for cutting, heating, or pinpointing a spot on the surface of a material. Without the output couplers, there would be no "relationship" that would help direct the lasers in a specific direction. 

Pipe Couplers and Pipelines in Factories

Pipe couplers are used to join and/or extend pipelines in factories. These couplers typically resemble small pieces of pipe, but there may be additions on either end of the couplers. These additions provide a conversion coupling to adjust the shape, size, and direction of the pipelines. In a factory setting, couplers are essential for the flow and control of chemicals, water, and gases. Not surprisingly, the conversion couplers are referred to as "male" or "female" conversion couplers, which only goes to show how relationship coupling extends to objects in the everyday environments you encounter. 

What Else Is Coupled?

Take a real good look around you. You will easily discover other objects that have couplers and other machinery that is coupled together with easily identifiable coupler components. It is an entirely new view of all things old and things taken for granted.