Glossary

SIM

A subscriber identity module is a removable smart card for mobile phones. SIM cards store the required information to identify the mobile device. It also contains data required for voice encryption to make listening in on calls almost impossible (except when the wireless carrier itself is doing the eavesdropping).

In this way the customer ID (and personal number) is tied to the SIM card and not to a certain mobile phone. This allows for a seamless interchange of the same SIM card between different GSM mobile phones.

SIM cards also serve as storage for SMS messages and the user's contacts. Current SIM cards can store up to 250 name/number pairs and up to 50 SMS text messages.

The SIM card cannot store multiple numbers per contact or other more complex information. This means that if you copy your contacts info from the phone memory to the SIM memory, contacts get broken up into as many entries as there are numbers for each individual contact and discards the other information.

All GSM phones and most iDEN phones require a SIM card to operate.

There are certain types of phones (CDMA, TDMA, AMPS) that do not use a SIM. Instead, the required data is programmed directly into the phone.

The SIM cards come in four standard sizes:

  • Full-size (85.6mm 53.98mm 0.76 mm)
  • Mini-SIM (25mm x 15mm x 0.76mm)
  • Micro-SIM (15mm x 12mm x 0.76mm)
  • Nano-SIM (12.3mm 8.8mm 0.67mm)

The first to appear was the full-size or 1FF (1st Form Factor), the size of a credit card (85.60 mm 53.98 mm 0.76 mm). It was followed by a mini-SIM or 2FF (2nd Form Factor), which has the same thickness but is 25 mm long by 15 mm wide, with one of its corners cut to prevent misinsertion. Next came micro-SIM or 3FF (3rd Form Factor), with dimensions of 15 mm 12 mm.

In 2012 the nano-SIM or 4FF (4th Form Factor) was introduced, which measures 12.3 8.8 0.67 mm. Nano-SIM cards can use adapters to gain compatibility with devices with Micro-SIM and Mini-SIM slots. A Micro-SIM card can also be fitted in Mini-SIM slot with an adapter.

There are two numeric passwords associated with a SIM card. One is the Personal Identification Number (PIN) that the user must input each time they start the device (this can be turned off via the phone settings).

When entering the PIN number the user has only three input attempts. If all three are incorrect, the card gets locked and a PUK (Personal Unblocking Key) must be entered in order for the card to work again. Only ten attempts to enter the PUK are permitted before the card is permanently locked and made unusable.

Related terms:

0 - 9

2G | 3G | 802.11

A

A-GPS (Assisted GPS) | A2DP (Advanced Audio Distribution Profile) | AAC (Advanced Audio Coding) | Accelerometer | Airplane mode | Alarm Clock | Alphanumeric | AMOLED display (Active-matrix organic light-emitting diode) | Analog | Android | ANT+ | Antenna | APN (Access Point Name) | Apple iOS | aptX | Audio jack | Auto-focus | AVRCP (Audio/Video Remote Control Profile)

B

Bada OS | Band | Bandwidth | Bar | Base Station | Benchmarking | Bit | BlackBerry OS | BlackBerry Playbook OS | Bluetooth | bps (Bits per Second) | Brand | Broadband | Browser | Byte

C

Calculator | Calendar | Call alerts | Calling Plan | Camera | Capacitive Touchscreen | Car Kit | Carrier | CDMA (Code-Division Multiple Access) | CDMA2000 | Cell | Chipset | cHTML (Compact HyperText Markup Language) | CIF (Common Intermediate Format) | Clamshell | CMOS (Complementary metal-oxidesemiconductor) | Color depth | Concatenated SMS | Corning Gorillla Glass | CPU (Central Processing Unit) | Crosstalk | CSTN (Color Super Twisted Nematic) | CTIA | Custom ringtones | CyanogenMod

D

D-Pad (Direction Pad) | DC-HSDPA (Dual Carrier or Dual Cell High-Speed Downlink Packet Access) | Digital Zoom | Display type | DLNA (Digital Living Network Alliance) | DNSe (Digital Natural Sound engine) | Downlink | DRM (Digital Rights Management) | Dual-band | Dual-Mode | Dual-SIM | DVB-H (Digital Video Broadcasting - Handheld) | Dynamic Memory

E

EDGE (Enhanced Data for Global Evolution) | EDR (Enhanced Data Rate) | EGPRS | EGSM (Extended GSM) | Email client | EMS (Enhanced Message Service) | EV-DO | EV-DV | Exchangeable covers | External Antenna Jack | External Display

F

FCC (Federal Communications Commission) | Feature Phone | Femtocell | Firefox OS | Firmware | Fixed-focus | Flash Memory | Flight mode | Flip-down phone | FM Radio | FM Transmitter | Form factor | FOTA (Firmware Over-The-Air) | FPS (Frames Per Second) | Frame Error Rate | Frequency | FTP (File Transfer Protocol)

G

GB (Gigabyte) | Gbps (Gigabits per second) | Geo-tag | GPRS | GPS (Global Positioning System) | gpsONE | gpsOneXTRA Assistance technology | GPU (Graphics Processing Unit)

H

H.263 | Half-QWERTY keyboard layout | Handwriting recognition | Haptics | Hot Spot | Hot Swap | HSCSD (High-Speed Circuit Switched Data) | HSDPA (High-Speed Downlink Packet Access) | HSDPA+ (High-Speed Downlink Packet Access Plus) | HSP (Headset Profile) | HSUPA (High-Speed Uplink Packet Access) | HTML (Hypertext Markup Language) | Hz (Hertz)

I

iDEN (Integrated Digital Enhanced Network) | IMAP (Internet Message Access Protocol) | IMEI (International Mobile Equipment Identity) | IP (Internet Protocol) | IrDA (Infrared Data Association)

J

Java

K

KB (Kilobyte) | Kbps (Kilobits per second) | Key Guard | Key Lock Switch

L

Land line | LCD (Liquid Crystal Display) | LED (Light-Emitting Diode) | Li-Ion (Lithium Ion) | Li-Polymer (Lithium Polymer) | LiMo OS | Linux | Location-Based Services (LBS) | Lock code | Long SMS | Long term evolution (LTE) | Loudspeaker

M

Macro | Maemo OS | mAh | Mass Storage mode | MB (Megabyte) | Mbps (Megabit per second) | MeeGo OS | Megapixel | Memory card slot | Memory effect | Messaging | MHz (Megahertz) | Micro USB | microSD | microSDHC | Microsoft Exchange (Server) | MIDI (Musical Instrument Digital Interface) | MIDP (Mobile Information Device Profile) | Mil-Spec (MIL-STD) | MIMO | Mini-USB | miniSD | MMC | MMCmobile | MMS (Multimedia Messaging Service) | Mobile games | Mobile High-Definition Link (MHL) | Mobile IM (Instant Messaging) | Mobile WiMAX | Mobility DisplayPort (MyDP) | Modem | Monochrome | MP3 (MPEG Layer 3) | MPEG (Motion Picture Experts Group) | MPEG-4 video | Multitouch input method | Music playback time (battery life) | Music Player

N

NAND Memory | Network capacity | Network coverage | NFC (Near Field Communication) | NiCd (Nickel Cadmium) | NiMH (Nickel Metal Hydride) | NOR Memory | Numeric keypad

O

OEM (Original Equipment Manufacturer) | OLED (Organic Light-Emitting Diode) | Optical Zoom | OS (Operating System) | OTA (Over-The-Air)

P

Packet Data | Pager | PC Sync | PCS (Personal Communications Service) | PDA (Personal Digital Assistant) | Phone Book Access (PBA) | Phonebook | PIM (Personal Information Manager/Management) | PIN code (Personal Identification Number) | Pixel | Pixel density (PPI) | Polyphonic ringtones | POP3 (Post Office Protocol) | Port | Predictive text input | PTT (Push-To-Talk) | PUK Code (PIN UnlocK Code) | Push

Q

QCIF (Quarter Common Intermediate Format) | Quad-band | QVGA (Quarter Video Graphics Array) | QWERTY keyboard layout

R

RAM (Random-Access Memory) | RBDS (Radio Broadcast Data System) | RDS (Radio Data System) | Resistive touchscreen | Resolution | Ringer ID | Ringing profiles | Ringtone | Roaming | ROM (Read-Only Memory) | RS-MMC (Reduced-Size Multi Media Card) | RSA (Rural Service Area) | RSS (Rich Site Summary) | Ruggedized (Rugged)

S

S60 user interface | SAP (SIM Access Profile) | SAR (Specific absorption rate) | Screen protection | SD (Secure Digital) | Secondary camera | Sensors | Side Keys | SIM | SIM lock | Single-Band | Skin | Slimport | Smartphone | SMIL | SMS (Short Messaging Service) | SNS (Social network service) | Soft keys | Soft Reset | Speed Dial | Stand-by time (battery life) | Stereo Speakers | Streaming Video | Stylus | Sub-QCIF | SVGA | Symbian | SyncML

T

Talk time (battery life) | TCP/IP | TD-SCDMA (Time Division-Synchronous Code Division Multiple Access) | TEST | Tethering | Text messaging (texting) | TFD (Thin Film Diode) | TFT (Thin Film Transistor) | Theme | To-Do list | Touchscreen | Trackball | Transflash | Transflective | Tri-band

U

UI (User Interface) | UIQ | UMA | UMTS | Unlocked phone | Upload | UPnP (Universal Plug and Play) | USB (Universal Serial Bus) | USIM

V

VGA (Video Graphics Array) | Video call | Video Codec | Voice dialing | Voice mail | Voice memo | VoIP (Voice over Internet Protocol) | VPN (Virtual Private Network)

W

WAP (Wireless Application protocol) | WCDMA(Wideband Code Division Multiple Access) | webOS | Wi-Fi | Windows Mobile | Windows Phone OS | Wireless email | WLAN | WMV (Windows Media Video)

X

Xenon flash