Editing Personal identification number (section)

=== PIN length===
The international standard for financial services PIN management, [[ISO 9564]]-1, allows for PINs from four up to twelve digits, but recommends that for usability reasons the card issuer not assign a PIN longer than six digits.<ref>[http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=54083 ISO 9564-1:2011 ''Financial services &mdash; Personal Identification Number (PIN) management and security &mdash; Part 1: Basic principles and requirements for PINs in card-based systems''], clause 8.1 PIN length</ref> The inventor of the ATM, [[John Shepherd-Barron]], had at first envisioned a six-digit numeric code, but his wife could only remember four digits, and that has become the most commonly used length in many places,<ref name=milligan>
{{cite web
  | url=http://news.bbc.co.uk/2/hi/business/6230194.stm
  | title=The man who invented the cash machine
  | publisher=BBC
  | access-date = 2014-06-15 | date=2007-06-25}}
</ref> although banks in Switzerland and many other countries require a six-digit PIN.