Lessons the tech world learned in 2012

LESSON 1 Tweet in haste, repent at leisure

Who would have thought that an elderly Tory peer would become a leading innovator in internet law? Yet that is what Lord McAlpine has become

Lord McAlpine tweeted and re tweeted when he was accused of child abuse. this changed the legal landscape in the UK.

Everyone who discriminated him had to pay compensation charges in court,among the latter was Sally Bercow, Mr Speaker's lively spouse

Twitter gives broadcast-type communication power to ordinary citizens and if a broadcasting network such as the BBC can be held responsible for what it transmits, surely Twitterers should be too?

LESSON 2 Valuing technology companies remains an inexact science

Facebook shares fell 24% in the first three days of open trading

paid for software firm Autonomy. In October 2011, HP bought the Cambridge-based company for $11.7bn.

HP announced that it was taking an $8.8bn write-off because it had realised that Autonomy was not worth anything like its purchase price. HP claimed that $5.5bn of the write-off was explained by the discovery of "accounting irregularities".

LESSON 3 Raspberries come in unexpected flavours

Eben Upton and some of his academic colleagues in Cambridge University's Computer Laboratory became concerned about the fact that most of the kids who wanted to study computer science no longer knew how to program. So they had the idea of designing a small, cheap computer that they could give to prospective students at open days

When Raspberry Pi, for that is what the device was eventually christened, was announced, 100,000 people joined the mailing list. When it went on sale, the demand crashed the servers of the two major online retailers that had signed up to sell it

it has sold more than 800,000 units and stands as an astonishing rebuke to the sceptics who said that in these days of iDevices and tablets there was no market for a device that ran Linux and simply sat blinking at you when you switched it on. But then that's what they also said about the BBC Micro.