Def1.) a trademark is a distinctive mark symbol or slogan used by a business to identify and distinguish its goods from products sold by other.
Def2.)A symbol, word, or words legally registered or established by use as representing a company or product.
Who and how to get it
Larger companies can get trademarks easier but it is not limited to them New or smaller companies can get trademarks also.
You must apply for a copyright at a court house or on trusted online copyright centers. A trademark only lasts 10 years then it must be renewed.
Specific rules of permission is given to people to use these trademarks such as a sponsership. showing a trademarked logo in a movie for a negotiated amount of money.