A YouGov poll conducted on behalf of Microsoft has found that almost half of us are concerned about personal information being collected online. Date of birth, gender and demographic information such as age and ethnic group were among the details survey respondents believed to be of most value to marketeers and black marketeers.

Worryingly, given the popularity of online personal banking and shopping, just 15 percent thought their web passwords were of commercial interest. Given the efforts of phishing sites and phishing emails to try and fool users into handing over information enabling access to financial and personal information, this is a surprising revelation.

Similarly, only a tenth of people thought their email addresses were useful to others - even though spoofed email addresses are a known method for hackers to solicit company or personal data from others. Several security companies have warned of the prevalence of email 'spoofers' who send out fake emails purporting to be from someone else within an organisation and exploiting the implicit trust of an apparently known sender to solicit sensitive data.

On a more encouraging note, the YouGov survey found that 80 percent of us are aware that our online surfing habits are being recorded by the sites we visit – which should mean we then limit the information we give out.

While many of us are aware of cookies – small programs that note where we go online and use it to note our preferences as well as surfing habits – 61 percent of survey respondents professed themselves concerned or very concerned that what they do online is monitored.

Most respondents said internet service providers, the websites visited, advertising and marketing agencies as well as search engines all collected information about us online, while 44 percent were convinced that the government does so too.

The high level of awareness about the fact that web surfing is a process that's routinely tracked shows we're fairly savvy about how the web works, but we're not necessarily prepared to take steps to protect information we provide online. A third of respondents said they believed the main responsibility for protecting our information and data online is down to the individual. However, just as many thought it was the ISP's responsibility.

In total, 67 percent thought online privacy and security was the responsibility of someone else.

While moves are afoot in the European parliament to bring in legislation to better control elements of the web, including data sharing and retention, once information we've voluntarily shared online or has been illegally shared by phishers, there's very little consumers can do to claw back their privacy once their personal details have been leaked.

Tony Neate, managing director of Get Safe Online, explained that while it may be possible to remove your own information from a single site, once that information has been picked up by spiders (automated tools that trawl the web for information on web pages and use it to compile results in search engines such as Google), there's no way of undoing the links and getting rid of that information.

Neate warns that 25 percent of us have put personal details about ourselves on social-networking sites such as Facebook and MySpace, while 15 percent of people have had personal information about themselves posted online by others. A typical example, said Neate, was of a party or family occasion that tagged people in the photos and that may include details of where they live and their ages.

The YouGov survey was conducted this August and questioned British adults about their awareness of web privacy issues.