1G
The first thing you should know is that the G in 5G, 4G, 3G, and 2G stands for Generation. What about the 5? Before we explore that, let’s take a trip back to 1979, in Tokyo, Japan, when it was 1.
Nippon Telegraph and Telephone, NTT of Japan, launched the world’s first commercial mobile phone cellular telecoms network on December 1, 1979. It was the first time a caller just dialed the number, and no human switchboard operator was needed to connect the call.
It wasn’t called any G at this point. It was just an analog mobile cellular phone mostly built into cars and too heavy to be carried around by users. It could transmit voice – low-quality – from mobile location and that was all that mattered.
2G
In 1991, 22 years after the NTT technology spread across most of the world, Finland launched a mobile network that established the 2nd generation of mobile networks.
The Finnish network was based on an emerging standard, the Global System for Mobile Communications, originally called Groupe Spécial Mobile or GSM.
To differentiate this from the NTT technology, this standard was dubbed 2G thereby implicitly christening NTT’s 1G.
2G introduced digital signaling within the radio network. It came with circuit-switched mobile data services like text messaging, and packet delivery at 9.6Kbits/sec.
With this network, it will take you about 14 hours to send a 1Mb picture to a friend in the same city assuming it was just the two of you on the network.
In the mid-1990s, the General Packet Radio Service, GPRS, was introduced to the GSM standard and the first wireless internet access became possible. The packet delivery rate grew to 172Kbit/sec.
The addition of GPRS to 2G was named 2.5G.
A few years later, the standard was enhanced by EDGE – Enhanced Data rates for GSM Evolution. EDGE networks became 2.75G and were first launched in the U.S. in 2003.
In its lifetime, the 2G Standards described technologies that could achieve between 100-400 Kbits/sec data rate and 300-1000 ms latency.
