Audio is sound, or rather a general term used when talking about sound and sound reinforcement, recording and reproduction. Sound is sometimes created intentionally by people to produce music. Some times sound is produced for communication like talking. Sound can even be intentionally created with mechanical or electronic devices to enhance a desired experience, like the frightening or startling noises at a carnival's haunted house, or setting a mood with soft music during a romantic dinner, or creating a sense of desolate space with wind sound blowing through brush in a western genre motion picture.
NEW - (sort of) Below is a link to a tutorial flash presentation that I made a few years ago. Here I am making it avaible to you for free.
Intro to Audio Tutorial
If you like it or think it can be improved let me know,
Because of modern technology we can record these sounds to be played back at a latter time. Music recordings are of course of great interest to many people but recorded audio can also be paired with recorded image (photographs) to create cinema (cinema). Contemporary recording equipment is small relatively inexpensive and produces very high fidelity recordings. The latest in digital audio recorders have created new possibilities of capturing sounds more easily than ever before.
The act of recording desired sound has become problematic. In contemporary mechanized cultures sound has become so prevalent as a by-product of other endeavors that areas of dense or even moderately populated areas suffer from sound pollution. In offices, homes, city and small town streets, sounds from computers, fans, heating and ventilating systems, automobiles, aircraft, neighboring entertainment, refrigerators, power tools, kitchen appliances and other devices all contribute to a constant raging din that is nearly completely pervasive in contemporary civilization. This makes acquiring clean, pure, audio recordings nearly impossible. The only exceptions to this are recording in specially designed sound proof recording facilities or at very remote rural or wild settings.
People who use recorded sound to create an artful or entertaining experience for an audience are often called Sound Designers. Sound Designers have to struggle to create convincing sonic experience for audiences. In everyday life the average person's attention has been refocused on image and away from the constant barrage of sound in their day to day lives. The buzz and hum of the office, and rumble of constant traffic goes seemingly unnoticed. Even police sirens fail to arouse awareness, let alone interest, in pedestrians in densely populated areas. However, when people find themselves in a theater or auditorium, or a home listening environment they are still able to be, even intent on being, aware of the design of sound. So care must be taken on the part of the sound designer to create a thoughtful and detailed experience for the intended listener.