(Ann Brown @ BBCnews) Online fraud can be very convincing, even to the wary

Fraud is aimed at everyone and every part of society, Government at every level, businesses large and small, charities and individuals.

A Fraud Action report in 2012 put the cost to the UK economy at £73bn, and of that £6.1bn a year is the cost to individuals.

I was a victim of a very plausible fraudster in the run up to Christmas, and that is the basis of The Investigation on BBC Radio Scotland.

A phone call at home asked if I was Mrs Brown. Being used to calls trying to sell me everything from PPI inquiries to home improvements, I am always on my guard and ask who wants to know.

This caller introduced himself as Michael Scott from the Visa Verification Fraud Team.

Did I, he asked, know there had been some unusual activity on my account that morning, and had I set up a payment of £5,000 to a George Sim. I'd been at a meeting all morning, hadn't been into my online banking, and had never heard of anyone of that name.

But, being the wary soul I am, I told the caller I wouldn't speak to him but would call the bank back. He immediately agreed that that was exactly what I should always do.

Nothing roused my suspicions about the call to the number shown on the back of my card; there was a normal dialling tone, then ringing tone, and the phone was answered in precisely the way I expected of the bank.

This time I was talking to John Turner. He confirmed the activity there had been on my account, and we spent some considerable time going through everything.

He told me not to use my card again, and said the bank would send me out a new card and pin within 48 hours. I was happy that any illegal use of my account had been averted.

But it was all a fraud, which I discovered when I spoke to the real bank the next day. My accounts had been wiped out, a loan set up for £10,000 and my phone number changed.

The bank refunded all my money - which they will do providing it's a genuine fraud and the customer hasn't taken any action themselves.

Primary Head Teacher JennieTracy experienced much the same type of scam, and at the fraudster's instructions, set up a new - supposedly secure - account to transfer all her money into.

She lost a total of £13,000 which her bank won't refund because she took the action herself, even though she believed she was talking to the bank.

The bank's advice is clear: don't ever call straight back on the same phone, the fraudster may be still on the line, so wait 10 minutes - or use another phone.

The bank says they would never ask someone to use a card-reader over the phone - the fraudster had done this, and I did use it.

This gave him access to everything. And of course, don't ever give your PIN number, passwords or the security number on the back of your card to anyone.

As technology advances, fraudsters have become increasingly sophisticated, and online fraud comes in many forms.

Scammers use fake letters, emails and phone calls, with the intention of getting hold of as much information as possible, particularly bank details, so they can get into accounts and strip them.

These are generally known as phishing. They might con people into spending money to claim a lottery win or a prize, or to take advantage of a fantastic special offer; they clone retail or even Government websites which look like replicas of the real thing, but if you look hard enough there are very small differences that should make shoppers beware.

Neil Coltart, Group Manager for Trading Standards with Glasgow City Council advises potential shoppers to make sure the web address starts with https - with the s meaning security, and there should be a padlock icon there as well.

Cloned Government websites include the Passport Office, where renewal is offered on line, and payment taken on the site.

Thousands are being duped by this one, including heads of government departments, senior journalists and business owners, all getting their new passports as they book their holidays.

One was even threatened with legal action if he tried to get his money back. The genuine Passport Office, while providing renewal forms online, does not take payment that way.

Other cloned Government websites include HMRC, the DVLA, and the European Health Insurance Card - which is charged for by the fake site, but is actually free in the UK.

The message from police, banks, Citizens Advice and Fraud Action organisations, is never give your personal details to anyone unless you are 100% sure of who they are.