Jeremy and Karen are personas representing a married couple with 4 kids aged 3-12. Jeremy works in insurance and Karen works in a building society. They have a combined high salary and live in the suburbs. Karen is socially active and involved with the kids' activities while Jeremy focuses more on work but catches up with the kids on weekends. The document discusses debates around the usefulness of personas and provides three techniques for building personas through user interviews: the fishbowl, empathy map, and pain/gain map.