How we are being watched

This RFID tag could be watching you

There are up to 4.2m CCTV cameras in Britain - about one for every 14 people - making it one of the most watched places on earth.

Legal and logistical obstacles stand in the way of a massive Big Brother-esque database but information is being gathered on almost everything we do.

Everything from shopping tags to mobile phones has the potential to be watching us.

CCTV CAMERAS

CCTV in Britain's streets can trace its genesis back to a limited system set up for the Queen's coronation in 1953. By the 1960s there was permanent CCTV in some London streets. Now there are an estimated four million cameras in the country, viewing us as many as 300 times a day.

CCTV is everywhere

CCTV cameras in stores monitor shoplifters, those in cash machines look for fraud gangs, those on public transport watch vandals and thugs. But they also watch ordinary people at the same time.

Digital CCTV systems can be configured to use face-recognition and look for criminal suspects.

An estimated £500m of public money has been spent on installing CCTV in the last decade.

AUTOMATIC NUMBER PLATE RECOGNITION

Cameras that could recognises the registration plates on suspect vehicles were first used to track IRA suspects in London. Now the technology is used for speed cameras, traffic enforcement cameras and in London's congestion charging zone.

SHOP RFID TAGS

A massively growing area of surveillance technology is radio frequency ID tags. Shops and logistic firms say they will eventually be vital in stock control, with products communicating to "smart" shop shelves that they are being picked up and that a replacement should be readied in a warehouse.

Tags are either active or passive.

Passive tags can be small, with no antenna or power source they are little bigger than a full stop. With an antenna, they are the size of a postage stamp. These passive tags need to be scanned by a radio reading device to reveal their information.

Tesco has led the way on RFID

Active tags are much larger, battery-powered and with a lifetime of up to a decade. Often used to track items such as freight containers, they have a range of hundreds of metres.

The fear is that RFID could eventually be used to monitor every object bought from a shop. But those behind the technology point out that their current use is for surveillance of objects only and that this stops at the door of the shop.

Perhaps the most controversial use of RFID to date in the UK was in 2003 when an RFID tracking system was used in the packaging of Gillette Mach3 razor blades to stop shoplifting at one of Tesco's Cambridge branches. Anyone picking up a packet of the blades triggered CCTV surveillance of themselves in the store.

MOBILE PHONE TRIANGULATION

As well as being used to monitor unfaithful spouses, the mobile phone has had a more direct application in crime-fighting.

In addition to requesting lists of calls to and from suspects mobiles, the police now frequently use mobiles' communication with different masts to triangulate the position of a suspect.

This has proved crucial in convicting Soham murderer Ian Huntley and Stuart Campbell, who killed teenager Danielle Jones.

STORE LOYALTY CARDS

There are anything up to 160 store loyalty card schemes in the UK, collecting information on shoppers.

The biggest scheme, Nectar, collects only data on how much is spent and where and when, but there is potential for other operators to eventually establish shopping habits by matching products to demographic information and tailoring offers to individual customers.

CREDIT CARD TRANSACTIONS

Every time we buy something with a credit or debit card we let the firm know where we are and what we are buying.

Information can be held on our spending patterns and also on our reliability as a customer. This can come in useful when an unusual pattern - such as spending a large amount of money in a foreign country - can be used to quickly identify that cloning or theft has taken place.

OYSTER CARDS

Introduced on London's public transport network to speed up the flow of passengers, data from the card is already being used by the police.

If a criminal has used his or a stolen Oyster, that can be matched to Tube station CCTV at the same time to establish a link.

SATELLITES

No-one outside the military and intelligence community really has any idea of the level of monitoring from the skies.

But the popularity of Google Earth must lead users to guess that the military probably have their hands on something a whole lot better.

ELECTORAL ROLL

It is illegal not to register to vote in this country, although many people choose not to for various reasons and avoid punishment.

The result of registration is the electoral roll - a public record of where each voter lives that has proved a goldmine to junk-mail firms, marketing people and journalists over the years.

The electoral roll can help the junk-mailers

Now Britons have the option not to appear on the publicly-available list and instead only to appear on a restricted version for the use of the authorities. But credit reference agencies successfully argued that they should have access to this unabridged version.

The electoral roll provides a history of every place you have ever lived. Choose not to register and you will struggle to get even the smallest amount of credit.

NHS PATIENTS RECORDS

The government is in the middle of a massive IT project to unite the NHS's various computer systems. Among the most significant developments is the bringing together of patient records on a national database.

Access to the records is carefully restricted, but privacy campaigners worry that the national system could prove vulnerable to security breaches.

PERSONAL VIDEO RECORDERS

Personal video recorders such as the TiVo or Skyplus offer a unique type of surveillance - they watch what you want to watch. The machines monitor your viewing habits and second-guess what you might want to record.

It's rather like the way TV viewing figures have been assessed over the years, where a select group have their televisions fitted with boxes to see what they are watching.

PHONE-TAPPING

One of the most burning issues facing the criminal justice system is how long it will be before wire-tap evidence - the intercepting or monitoring of a mobile or landline telephone - is allowed to be used as evidence in court.

The government and the intelligence community are currently against - they do not want to be forced into making public evidence that could compromise security operations. Among those in favour are campaign group Liberty and legal reform group Justice.

BUGS AND HIDDEN CAMERAS

While phone-tap evidence cannot be used in court, evidence from bugs can. The first bug was invented by Russian Leon Theremin and after being discovered in the US embassy in Moscow, was reverse engineered by Spycatcher author Peter Wright.

This venerable method of surveillance was in the news again recently when it was revealed a London restaurant was sweeping for bugs to prevent industrial espionage involving corporate lunches.

WORKER CALL MONITORING

While there are few who will ever be recorded by a bug, there are thousands in the UK who have their phone conversations recorded every day.

Call centre workers, whose conversations are recorded for "training purposes", face daily eavesdropping from managers keen to ensure they do not diverge from the script or indulge in too much personal chit-chat during sales calls.

COOKIES

One of the most subtle forms of surveillance is the use of HTTP cookies - small packets of data that are used to communicate between websites and your computer. They are used to set your preferences when you visit a website for a second time and for a host of other reasons.

You can switch your cookies off but then there's a host of websites that you will be unable to use properly. Want to shop online? Well then you might just have to accept being watched.