Many researches tried to define the concept of Brand Equity.
Initial definition characterized it as the added value the brand gains as a result of investing in a branded marketing (Aaker 1991; Farquhar 1989 Srivastava and Shocker 1991 & Lutz (2002) Moore, Wilkie ).
Yoo , Donthu &, Lee (2000) defines brand equity as the equity differences between two similar products. This definition deals with two brands gaining the same utility benefits, with a different brand name. This brand name gives the product its unreal benefits.
Herman ( 2001)as well defines brand equity as benefits that are above the products utilities. Those are psychological advantages (defined by the consumer itself), social advantages and even experience benefits.
Herman gives an example by mentioning the Coca Cola test- The difference the consumer experienced while tasting a glass of Coca Cola from a transparent glass, when the drinkers did not know the name of the drink, and the different experience they had while drinking from a Coca Cola bottle.
Same drink, same glass, brand name was exposed in one of the options. Many researches demonstrated that the glass poured from the Coca Cola bottle was tastier than the other (Herman, 2000).

Those definitions are not contradicting and all of following definitions by Yoo , Donthu &, Lee (2000), Herman (2000) and Yoo , Donthu &, Lee (2000)are adding a new aspect by associating brand equity with all unreal benefits in a brand.
Many studies dealt with the need for brand equity, a concept that became a leading marketing concept in the past 20 years, all in order to answer the question of how to create a positive image, expand the brand into new categories and build brand loyalty (Aaker & Joachimstahler, 2000).

New technologies and new marketing methods are giving the consumer a better access to knowledge, more options and less switching expenses, all of those are contributing to the need in brand equity.Today, consumers satisfaction is not determined only by the real utilities the product has, but also by the advantages given by the brands equity benefits.
Brands that do not have future brand equity can suffer from lack of loyalty and a small target market (Schreuer,2000).
According to Herman (2000), brand equity creates income steadiness, this gives the distributor time to patch up things in case of market changes.
This gives the brand the ability to be more than the product itself and justify a higher price and constant preference by consumers.

Faircolth , Capella & Alford (2001) analyses different aspects in brand equity while using empiric research and Aaker (1991) and Keller (1993) modules. Those modules demonstrate viewpoint influence and brand image on brand equity. Researches show that brand equity can be manipulative, by using association elements and different signs that can influence the brand image, and by doing so influence the brand equity.
Moore , Wilkie & Lutz (2002)studied whether brand equity can stay for long, meaning, can you pass brand equity from one generation to another.
In order to study the subject, they preformed 2 researches. The study showed that brand equity can sometime pass from on generation to another, and sometimes not. This result is due to changes in brand equity due to new influences in the consumer’s life cycle: environment, work place, social status, etc.
Myers(2003) defines another important aspect , in a study preformed in the USA, Myers studied the equity of nine leading brands in the soft drinks segment. The study findings demonstrate that brand equity is one of the most important factors that influence the consumer in each acquisition decision.
In light of multiple competitors in the market it was found that real equity and unreal equity was considered important for building brand image and acquisition intentions. Also, it was found that brand name is more important than brand’s utilities functions.
Wee & Ming (2003)supported Myers (2003) and indicated that in a competitive world like ours, brand equity is based on symbolic values.
Distributors create brands with symbolic values and “personality”, and while doing so, they become part of the consumer’s life. This branding procedure creates in the consumer’s mind a personal relationship between him and the brand itself.
In the empiric study, done by the researches, it was found that symbolic values are more important than operative values of the product.
The study shows, just like Myers (2003) study, the importance of unreal equity. Distributors can not relay on operational benefits any more, but, they need to create symbolic benefit and experience to the brand. For example: BMW is considered as a product that provides youthful and success values.