Glossary
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e-mail. In addition to the text content of SMS, MMS
messages can contain still images, voice or audio
clips, and in the future, also video clips and
presentation information.
Multiparty calling
Ability to establish a conference call involving up to
five additional parties.
PIN (Personal Identification Number)
Security code that protects the phone/SIM against
unauthorised use. The PIN is supplied by the
service provider with the SIM card. It may be a four
to eight-digit number and can be changed, as
required.
PUK (PIN Unblocking Key)
Security code used to unlock the phone when an
incorrect PIN has been entered three times in
succession. The eight-digit number is supplied by
the service provider with the SIM card.
Roaming
Use of your phone when you are outside your home
area (when travelling for example).
SDN (Service Dialling Numbers)
Telephone numbers supplied by your network
provider and giving access to special services, such
as voice mail, directory inquiries, customer support,
and emergency services.