1. arbitrary
2. suggestive
3. descriptive
4. generic

An arbitrary mark receives the most protection since the name bears no relationship to the product -- it implies imagination and thought. Kodak is an example of an arbitrary mark because the name itself suggests no connection to film or camera equipment. We learn this association only after the name has been used and becomes associated with the source of that product. A descriptive mark receives protection if it has secondary meaning in consumers' minds. A generic mark rarely receives protection because it is naturally associated with something in consumers' minds. An ordinary description is not special enough to warrant protection. However, if consumers connect the mark and its source in a way that would not exist without the mark's use in commerce, then the mark can be protected.

Alphabet letters, initials, abbreviations and acronyms may be entitled to protection if they are so original that they constitute an arbitrary mark (e.g., NICAD for nickel cadium). Otherwise, they may be protected only if they had acquired a secondary meaning which means that consumers have come to recognize the mark and associate the goods with a particular manufacturer (e.g., IBM and BMW).

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