Such is the secret of 2G -3G-4G

As human PD continues to develop. The same is the SIM used on mobile
There are a lot of older ones. Which we call 2G, 3G, 4G, 5G. In general, we refer to SIM's GENERATIONS, namely, 2G, 3G, 4G, and 5G. Just as the new generation is more familiar with the Internet and science fields than the older generation, 4G rather than 3G is new in terms of GENERATION, so the ability to work in 3G over 2G is greater.
And the internet has the potential to work over 2G and 3G over 3G, but we can easily feel that way.
         There is no doubt that 2G 3G means 4G and 5G Second Generation, Third Generatio, Fourth Generation, 5th Generation of SIM.