Demographic: Observable differences/similarities, including age, gender, family size, household income, employment status, etc.
Firmographic: Like demographic market segmentation for B2B companies.
Psychographic: Considers the values, priorities, beliefs, etc., of the target audience.
Behavioral segmentation: How customers behave both online and in physical stores.
Geographic market segmentation is also a valuable market segmentation option. Although this can come under demographic segmentation, many marketers would look at the geographics of their target audience as a category in itself.