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Technology: Engineering Our World
The exchange of information or ideas between two or more living
beings is known as communication. This is a big word for a simple act. It
came from the Latin, communo. It means to “pass along.”
Communication is more than just sending a message. The message
must be received and understood. If this does not happen, there is no
communication. Communication technology is the process of transmitting
and receiving of information using technical means. This chapter introduces
you to the skills and equipment used in many kinds of communication.
Types of Communication
There are three types of communication. All are based on our sense of
hearing and sight.
• Visual communication presents ideas in a form we can see. Thoughts
are changed into words, symbols, and pictures. Stoplights, street signs,
photographs, and books give out visual messages. See Figure 3-1.
• Audio communication consists of messages that can be heard but
not seen. A buzzer tells you class is over. A doorbell at your home
tells you someone is at the door. Telephones, radios, and CD players
rely on audio communication. See Figure 3-2.
• Audiovisual communication can be both seen and heard. You are
receiving audiovisual messages when you watch and listen to
television, DVDs, and movies.
gure 3-1. Some street signs communicate
a clear message to all people regardless
of the language they speak. What is being
communicated here?
gure 3-2. We hear messages that are transmitted using audio
communication. What sources of audio communication do you use?