The technology behind the mobile phone is celebrating its 20th anniversary.
On 7 September 1987, 15 phone firms signed an agreement to build mobile networks based on the Global System for Mobile (GSM) Communications.
According to the GSM Association there are more than 2.5 billion accounts that use this mobile phone technology.
Adoption of the technology shows no signs of slowing down with many developing nations becoming keen users of mobile handsets.
There was an article on last weeks BBC Click about this, apparently one of the competing technologies worked in a very similar way to Wifi, as in hotspots etc. Its good they never went that route, network coverage wouldnt have been good enough lol. BBC News Report