In 1973 during a public demonstration, a 30-ounce device was used to make the first call from a portable cell phone. Ten years later, Motorola introduced the first marketable cell phone weighing in at $3,500 and 16 ounces (the average cell phone today is about 3 ounces.)

The continually evolving cell phone, and its respective industry, is an insightful indicator of the technology revolution. As landlines become obsolete, industry leaders are compelled to streamline the phones’ technology, offering optimal ease and compatibility to the wide range of marketable consumers. They’ve even gone so far as to give phones a pseudo-brain power.

A SIM card, or Subscriber Identity Module, is the digital brain of a cell phone. The extractable information card can be slid out of an old phone and into a shiny new model – arguably the most appealing feature of a SIM card. This extraordinarily small memory chip holds ample amounts of information from personal identification information, phone numbers, text messages and other data. The newest, most popular version of the SIM card has a width of 25mm, height of 15mm and a thickness of 0.76mm.

The hassle free abilities allowed by a SIM card are a strong selling point amongst its cell phone carriers. Upgrades are hassle free and switching carriers is also a cinch, simply flip the SIM card into the new phone – provided of course that the phone is also SIM card compatible.

International travelers can also take advantage of a SIM card’s capabilities. Simply buy a local SIM card and avoid soaring costs of international roaming charges.

The only down side is that SIM cards can only operate on a network called GSM or Global System for Mobile Communication. Their competitor, CDMA or Code Division Multiple Access, formulated by Qualcomm, is not SIM compatible. In fact they carry their own memory card technology called R-UIM or Re-Usable Identification Module which will eventually be available worldwide.

On a positive note, as the cell phone market continues to be amplified by the technology crazed public experts say it is safe to assume that cell phone technology will have to eventually support both SIM and R-UIM. After all, technology as a business is based in fulfilling the ever-changing needs of the consuming public.

By: Maryann Loprete
Edited By: Bruce A. Tucker