[messaging] Social Security cards and additional issues

[Robert Ransom]

On 1/30/14, Watson Ladd <watsonbladd at gmail.com> wrote:
> Take your social security card: notice that the number is broken up
> into unequal blocks.
> The same is true for telephone numbers.

I'm not sure about SSNs, but the digit grouping for telephone numbers
used to mean something.  (The area code is still separate, but in
(xxx) yyy-zzzz, the yyy used to specify an ‘exchange’ within the area
code.  As of some recent time, there were also restrictions on which
digits could be used in each position within the xxx and yyy triples,
in order to make numbers dialed with an area code distinguishable from
those dialed without one.)

(Note: We're Americans.  Telephone numbers in other countries may have
a different structure, or none at all.)


Robert Ransom