Audio is a mechanical wave that is an oscillation of pressure transmitted through a solid, liquid, or gas, composed of frequencies within the range of hearing and of a level sufficiently strong to be heard, or the sensation stimulated in organs of hearing by such vibrations.

searchengineoptimization art businessservice resort entertainment webresorce computerservice athletic food book collectibles training outdoorrecreation webhosting photography auctionservice electronic commercial information music prescriptiondrug onlinedating communication travel realestate hotel hobby medical gift fun cloth family garden internetresource telecommunications computerhardware healthcare home pet education audio onlineshopping publication personalservice businessproduct webmarketing autocare financialservice health personalproduct industrial webdesign fitness religion homebasedbusiness e-commerce creditcard safety homeservice game culinary animal wedding employment internetmarketing legalresources homeproduct software security sport jewlery internetserviceprovider