Two-way communications systems are also routinely used in the construction and building trades, public transportation, the trucking industry, and aviation by commercial and non-commercial pilots, just to name a few.
Two-way communication systems vary greatly in sophistication and special features. They range from simple hand held two-way transceivers that use a single dedicated channel to more complex systems that allow a large number of users to share several channels. The type of system chosen depends on many factors, such as the intended use, the location, the number of users, the frequency band , and the cost of the system. Regardless of the type of system chosen, the one common feature is that all of the components must be compatible and work together to support a common purpose.