Brand – noun (brand): A product or service to which human beings attach a bundle of tangible (functional product and service characteristics) and intangible (emotional and/or symbolic) meanings that add value. A brand has one strategic purpose and that is to differentiate itself from competitors.
Now an example of a horrible rebranding strategy:
Which is basically this:
Older brands like Tropicana have the luxury of nostalgia on their side. Unlike the newer products that need to convince you why they matter and should be purchased by your hard earned dollar, older brands are able to use imaging, slogans and even packaging to touch a nerve in you and subconsciously if not overtly let you know that they are a staple.
Why Tropicana would so easily let that positioning go, who knows...
Thankfully Pepsi is phasing this atrocity out but read here and here for the back story and to see why this rebranding effort FAILED!