A copyright protects the expression of an idea, not the idea itself. For a work to be copyright able it has to be original to the author and it has to be fixed in a tangible medium of expression.
Copyrights also protect original expression of authorship. Now Trademark law protects business names, logos, catch phrases that some companies use to identify their products. The law wants those marks to be easily recognizable to the consumer so when she goes to buy a pair of sneakers she knows that the sneakers with the three stripes come from one company and the sneakers with the swoosh come from another company.
Copyrights also protect original expression of authorship. Now Trademark law protects business names, logos, catch phrases that some companies use to identify their products. The law wants those marks to be easily recognizable to the consumer so when she goes to buy a pair of sneakers she knows that the sneakers with the three stripes come from one company and the sneakers with the swoosh come from another company.