Branding is a way of communicating intangibles to customers, of creating and maintaining a distinctive image. Brands generate buzz that can make your company or products stand out and induce customers to take a second look.

What’s more interesting to you as a consumer: running shoes named after Nike, the Greek goddess of victory, or trainers made by the XYZ Company? Which presentation consultant sounds more intriguing: the generic John Smith or Eugene Moreau, who runs a company called 13 Boxes?

Note that unless Nike and 13 Boxes offer high-quality products and services and keep their customers happy, they could quickly lose them to XYZ and Mr. Smith or a host of other competitors. But their brands offer an advantage in drawing customers in the first place. A brand can do the same thing for you.

In today’s world of nearly infinite choice, it’s the brand that does the selling. Marketing and advertising are means of promoting your brand—but first you’ve got to create a meaningful brand to promote. Brands influence customers’ purchasing decisions, but only when they know what your brand means.

Help consumers out by keeping your brand tightly focused. Unwisely expanding your line just confuses people. Financial guru Peter Lynch called it “deworsification” when companies dilute their core businesses by expanding into unrelated fields, and the same can happen with brands.

Jack Daniels is renowned for its whiskey, so what possessed the company to introduce a beer with the Jack Daniels name? McDonald’s is the fast-food leader, with an undisputed appeal for kids. The burger giant stumbled by introducing the short-lived Arch Deluxe, a sandwich marketed for adults.

By keeping your focus on what you do best, you help maintain your brand’s identity and make it easier to take ownership of your category.

Let’s say your Bow-Wow doggie day-care service is going great guns. You’ve publicized the fact that all of your employees are trained by animal behaviorists, and now people think of your company as the service that really understands dogs. Think twice before you diversify into birdhouses and cat furniture. As soon as you do, you become an ill-defined, all-purpose pet-supply company. Why give away your niche and start competing with PETsMART?