DIALECT (or language variety) is a neutral term used to refer to any variety of a language shared by a group of speakers.
 
 

Languages are always made up of various dialects or varieties, and to speak a language is to speak some dialect of that language. Every speaker of a language speaks a variety or dialect of that language.
 

In this technical usage, there are no particular social or attitudinal evaluations of the term (no "good" or "bad"); it is simply how we refer to any language variety that typifies a group of speakers within a language.
 

The particular social factors that create this diversity may range from geography to social class or ethnicity.
 

Furthermore, it is important to understand that socially privileged or "standard" varieties are every bit as much a dialect as those varieties spoken by isolated, socially marginalized groups whose language differences are socially stigmatized.
 

Some Realities:

In positive and negative ways, people do judge each other by how they speak.  A dialect can identify one as part of the group, or it can stigmatize one as an outsider.
 

People often associate dialects with certain moral, intellectual, personal, or social characteristics.  More often than not, these associations are inaccurate stereotypes.  There is never a clear connection between how a person speaks and their moral or intellectual capacities.
 

While these judgements are often inaccurate, they are social realities in virtually every region of the world, including the United States.  We need to be consciously aware of how others measure us and how we measure others through speech.