ion, the relative rarity of impersonal transactions meant that they were more closely scrutinized. A bank teller might scarcely glance at the signature of a known customer, but might look more closely at the signature of an unfamiliar person, especially for a transaction involving significant sums of money. Out-of-town checks might not be accepted at all, even after showing identification such as a driver's license; "traveller's cheques" were developed precisely due to the high barriers to transactions involving unfamiliar persons.
Finally, what might be called "impersonal identifiers" -- the array of codes such as Social Security numbers, "PIN" numbers, account numbers, and so forth -- that are used to identify us in impersonal transactions, were limited in extent, interconnection, and availability. These provide the raw material of identity fraud, but until recently they were few in number and did not circulate widely.
Most people had only, perhaps, a Social Security number, a driver
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