Alan Freedman -- The Computer Language Company - Computer Desktop Encyclopedia
Computer Desktop Encyclopedia
Longest-Running Tech Reference on the Planet

A CDE Definition

You'll love The Computer Desktop Encyclopedia (CDE) for Tech Term of the Day (TTOD)

LOOK UP ANOTHER TERM


Nano SIM

The smallest subscriber identity module (SIM) card, which provides customer information for a cellular phone. See SIM card.




Nano SIM
This Galaxy S7 phone uses a single tray to hold both the Nano SIM for customer identity and a micro SD card for storage.






SIM card

(Subscriber Identity Module card) A smart card that gives a cellphone its phone number and customer identity. Introduced in 1991 for GSM phones, most cards are removable. Satellite and LTE phones also use SIM cards. Activated by the cellular carrier, the SIM card contains a unique ID, authentication codes, network-specific data and the customer's phone contacts. See IMSI.

As long as users stay with the same carrier, they can generally switch their phone number and calling plan to a different phone by moving the SIM card. For travelers, prepaid SIM cards are available for unlocked phones, and phones that hold more than one SIM are also offered (see multi-SIM). In the early 1990s when cellphones were large, the first SIMs were the size of a credit card (1FF). See eSIM, SIM lock, R-UIM and smart card.




Mostly Nothing
A SIM is just a chip behind contacts. The rest is cardboard. Used for a while were Micro SIMs in a Mini SIM form factor (right).



                   Size   Thick   Form
  SIM Card         (mm)    (mm)   Factor

  Full Size        86x54   .76    1FF
  Mini (Standard)  25x15   .76    2FF
  Micro            15x12   .76    3FF
  Nano             12x9    .67    4FF
  Embedded          6x9   up to 1





Mini SIM
This Mini SIM was removed and flipped over to show the contacts and the six pins they press against.






Open the Case or Slide Out the Tray
Access to a SIM card is either from the inside by taking the back off or by inserting a pin into the side of the phone that releases the tray.






Prepaid SIM Cards
For travelers with unlocked Android and other GSM cellphones, prepaid SIM cards can be purchased.






Mini or Micro
A SIM card may come in both Mini and Micro SIM formats that can be punched out as required.






Personal Use Only

Before/After Your Search Term
BeforeAfter
NANNano-X Window System
Nanchuknanochondria
Nanconananocomposite
NANDnanocrystal
NAND flashnanoelectronics
nanny softwarenanofactory
nannycamnanofluidics
nanonanoionic
nano-ionicnanojet
nano-satellitenanojuice

Terms By Topic
Click any of the following categories for a list of fundamental terms.
Computer Words You Gotta KnowSystem design
Job categoriesUnix/Linux
Interesting stuffPersonal computers
InternetIndustrial Automation/Process Control
Communications & networkingAssociations/Standards organizations
HistoryDesktop publishing
Audio/VideoGraphics
MainframesSecurity
ProgrammingHealthcare IT
System design