Tech News Desk – The use of mobile has increased very fast. When the phone came, understand that the SIM also came along with it. Without a sim, the phone is of no use. Simply put, since we’ve seen the phone, we’ve recognized the SIM as well. SIM is being used for years, but the question related to it will hardly be in anyone’s mind. Have you ever looked into The Sims? If yes, then you must have noticed that one corner of it is cut off. But do you know what is the reason behind this?
Subscriber’s identity Module (SIM) card is a removable electronic chip that is used to identify the subscriber in a mobile telephonic network. A SIM card is an electronic chip with an embedded microcontroller with memory. Sim cards have eight contacts embedded in the card. The SIM card used in mobile phones has a width of 25 mm, a length of 15 mm, and a thickness of 0.76 mm.
Types of SIM cards
SIM card has to be inserted according to the phone’s specifications. Its size can be small or big. Types of SIM cards are as follows.
- All SIM cards
- Micro SIM card
- Mini SIM card
- Nano SIM card
- Chip card
The use of mobiles has increased very rapidly and now many of our tasks come to a standstill without a phone. If you get a phone, understand that a SIM card also becomes indispensable. A phone is useless without a SIM. Simply put, we have been using SIM cards ever since we saw a phone. SIM has been in use for years, but a question related to it has hardly arisen in anyone’s mind. Have you ever looked closely at a sim? You must have noticed that one corner of it is cut off. But do you know the reason behind it?
Full Form of SIM Card
Do you know the full form of a SIM card? Let us say that the full form of SIM is Subscriber (S) Identity (I) Module (M). It is an integrated circuit running a Card Operating System (COS) that securely stores the International Mobile Subscriber Identification (IMSI) number and its associated key in its chip.
This number and key stored in the SIM card chip are used to identify and authenticate users on mobile telephony devices such as mobile phones and computers.
Standards
International Organization for Standardization(ISO) and International Electrotechnical Commission are the agencies that standardize SIM cards. The cards are standardized as per ISO 7816-1 describes the physical characteristics of cards and ISO 7816 part 2 defines the dimensions and location of the contacts(for details- visit).
Let’s a comeback to our topic. The main reason for the cut mark on the corner is to avoid the misalignment of the contacts of the SIM card and mobile phone cardholder pins. PIN 1 of the SIM card to make the contact with the corresponding pin of the mobile phone. The cut mark serves as a guide for the proper placement of cards in mobile phones. As it is internationally accepted by ISO, being followed by all mobile phone manufacturers.