A trademark is a sign that may help to distinguish goods or services of one company from those of other companies. This is more or less the standard definition of a trademark as used in the legal field. Other fields of science or business will use other definitions of what constitutes a trademark.

The two key words in the legal definition of a trademark are probably ‘sign’ and ‘distinguish’. A sign can be much more than one may expect. The most obvious signs or trademarks are words. Word marks can consist either of an existing term or a coined word. Other common marks are logos (or ‘device marks’) or a combination of one or more words and an image.

Other signs may also help very well to distinguish certain products from others. The label on a product, the colors and shape of the product or of its packaging and combinations of these may also fulfill this role. There are also less evident signs that may also function as trademarks like sounds or smells. The definition is not exhaustive. Again, basically any sign may be regarded as a trademark as long as it fulfills its distinctive role.

The other essential word is to ‘distinguish’. Not all signs are able to distinguish goods (or services) for various reasons. Words may describe the product itself or certain qualities or features for a product. In that case, such a word can by definition, not at the same time distinguish certain of those products from the same products from another company.

Other words were originally distinctive signs/trademarks but have become generic as a consequence of generic use of it. There are signs that are so commonly used that the public cannot distinguish goods from other goods, so they are simply non-distinctive.