What is the full form of SIM? What is a sim? | How does sim work?

What is the full form of SIM? What is a sim? | How does sim work?

SIM: Subscriber Identity Module or Subscriber Identification Module

Have you ever thought about what happens in the sim so that you can make phone calls and run the internet with increased ease Or have you ever thought what is this sim card, or how does sim work? Or what is the full form of the sim? If yes, then today you will get the answer to all your questions in this article.

Even if you haven't thought, you should definitely read this article. Because you have been using the SIM for many years, then you should have all the information about this SIM.

Today I will tell you what is the full form of Sim? How does sim work? Along with this, you will give all the information about the sim card.

What is the full form of SIM? What is a sim?
What is the full form of SIM? What is a sim?

What is the SIM Full Form?

Subscriber Identity Module or Subscriber Identification Module.

SIM Full Form In Hindi

In Hindi, it is also called customer identification modulus, but globally it is known as a sim card.

What is the sim?

The SIM card is an integrated circuit in which international mobile customer identification data is protected as a chip. It identifies people internationally. Actually, through SIM, your mobile network provider such as Vodafone, Airtel, Idea, Jio, Aircel, etc. can identify which number of services you are using. Through Sim Card, your network service provider can access the service to you more safely.

How does sim work?

Actually, the SIM card has an IMSI number which is a 64-bit number and its full form is International Mobile Subscriber Identity(ISMI) i.e. International Mobile Customer Identification. In addition, it has an authentication key.

When you insert a sim in your phone, the sim in your phone connects to the tower of your nearest network provider company. The tower then checks your SIM's IMSI number from its tower's database. After this, the authentication key in your SIM and the key of that tower are exchanged with each other, this will identify you and that tower from each other.

Your authentication key identifies you and the key of that tower identifies your SIM and tower. Apart from this, a long number is written on the back of your SIM. This number is ICCID ie Integrated Circuit Card Identifier, it is the identifier of an actual SIM card, this shows that it is a valid SIM card.

What is the type of Sim?

There are two types of SIMs. One is GSM and the other is CDMA and now LTE has also come.

GSM - Global System for Mobile Communication

GSM uses your SIM to keep phone details and numbers.

CDMA - Code Division Multiple Access

CDMA uses your phone's storage to keep your phone details.

LTE - Long Term Evolution

Today, LTE is being used the most.

What is Sim's history?

The first SIM card was created in 1991 by Munich's smart card makers Giesecke and Devrient. And the first 300 SIM cards were sold to the Finnish wireless network operator Radiolinja. When the SIM card was invented in 1991, it came to be almost like a credit card. The SIM card has three operation voltages of 5V, 3V, and 1.8V.

Most SIM cards launched before 1998 had a voltage of 5V. After that, the SIM cards that came in the market supported 5V and 3V and today's modern SIM cards also support 5V, 3V, and 1.8V.

What are Sim's fun facts?

Do you know that SIM cards come in different data capacities such as 8 KB to 256 KB? You can save up to 250 contacts in it.

What is the full form of SIM? What is a sim?
What is the full form of SIM? What is a sim?

Do you know that when the first sim was launched, it was in the shape of a credit card but as time progressed? It changed from full-size sim to mini sim then micro sim and then nano-sim and now after some time, this nano sim will also be discontinued. And e-sim will come.

Do you know that a part of the sim is sliced ​​so that AAP can directly insert the sim directly into the sim slot?

Do you know that every sim card has a serial number before which the first three numbers are the code of that country, followed by two numbers indicating the company whose sim card is and the last seven numbers are unique user id?

How many and which formats of Sim Card?

Sim cards have come in many formats in the past, such as full-size sim, mini-sim, micro-sim, and nano-sim and now e-sim is also in the works.

Full Size

It was introduced in 1991. It is also called 1FF i.e. 1st form factor. Its length was 85. 6 mm, width 53 .98 mm and thickness 0.76 mm. Its size was equal to a credit card.


It was introduced in 1996 and it is also called 2FF i.e. 2nd form factor. Its length was 25 mm, width 15 mm and thickness 0.76 mm.

Micro Sim

It was introduced in the year 2003. It is also called 3FF i.e. 3rd form factor. Its length is 15 mm, width 12 mm and thickness is 0.76 mm. In June 2010, the iPhone 4 was the first smartphone to use a micro-SIM card.

Nano Sim

Nano Sim was introduced in 2012, it is called 4FF i.e. 4th form factor. Its length is 12.3 mm, width 8.8 mm and thickness is 0.67 mm. In September 2012, the iPhone 5 was the first phone to use a nano-SIM card.


It has not been launched yet but it is the next generation of sim card. It will have a pre-embedded SIM device. You will not need to apply and remove sim. Even to change the sim, there will be no need to physically remove the sim. Because it is a software-based SIM card, the whole work will be the application itself.

Apple implemented e-sim in Apple Watch Series 3 and Second-Generation Ipad Pro. After this, in 2017, Google took the curtain from Pixel 2 and told that Pixel 2 has supported e-sim to use Google Fi service.

After this, in 2018 Apple launched the iPhone X and iPhone XR with the support of e-sim. iOS 12.1 or above is required to support e-sim on iPhone.

what is the full form of GSM?

  • Global System for Mobile Communication(GSM)

what is the full form of CDMA?

  • Code Division Multiple Access(CDMA)

what is the full form of LTE?

  • Long Term Evolution(LTE)

what is the full form of ISMI?

  • International Mobile Subscriber Identity(ISMI)

what is the full form of  ICCID?

  • Integrated Circuit Card Identifier(ICCID)

The conclusion

I hope you will like all the information about Sim Full Form and Sim. If you still have any problem or problem, then you can tell us by commenting below.

Baca juga

Post a Comment