Definition of "Brand Equity"

In Building Strong Brands, David Aaker defined "brand equity" as follows: 

Brand equity is a set of assets (and liabilities) linked to a brand's name and symbol that adds to (or subtracts from) the value provided by a product or service to a firm and/or that firm's customers. The major asset categories are:

1. Brand name awareness.
2. Brand loyalty.
3. Perceived quality.
4. Brand associations.

Branding is mostly about building and maintaining brand equity.