Supermarkets exist for one purpose, and that is to try to get you to part with your money, preferably much more of it than you intended. We tend to fool ourselves into thinking that they are providing us with a service, but it can also been seen as something of a game - a competition if you like - between the retailers' tricks and our own naivety in walking in as a victim and walking out without very much money left.

However, like any game, you stand much more chance of winning if you actually know the rules. Having a good understanding of the techniques that the shops use to try to entice you to spend more money will help you in preparing for your retail experience, and stand you in better stead.

Some of the techniques shops use are very traditional and have long histories which demonstrate a real success rate, and yet still we walk in completely oblivious to these tricks. We keep falling for them time after time. Like music, for example. Piped music can be considered irritating, but it exists in almost every shop. Why do you think that is? Is it because the retailer is concerned about our welfare, and as a service industry there to help us, music can help to soothe us and make us feel happy and comfortable? Surely it has nothing to do with parting us from our money?

Of course it does. The choice of music used has a deep and very significant impact on our mood and frame of mind, beyond our own awareness, and this can very much leave us vulnerable to the wily tricks of the trade. Some music can make us feel relaxed, calm and feeling as though we have all the time in the world. This clearly is an attempt to make us stay longer in the shop, spend more time looking and browsing, and noticing things we may otherwise have missed.

It has also been shown that some music can actually make us want to spend money! By creating a mood that makes us feel modern, part of a trendy modern society, positive and exciting, we can feel energised and enthusiastic about being a part of the image which the shop is showing us we can be.

The location of products also makes a difference. Displays at the end of aisles will be far more noticed, and even the positioning of aisles makes a difference. Ever wondered why you can't stand at one end of the shop and look straight down the aisle to the other end? Thought about why, when you try to do that, all you see is the display at the end of the aisle half way down the shop, because they've staggered the aisles? Of course, it's for that exact reason. Staggering the aisles makes you more likely to notice the displays at the end of each aisle.

It doesn't stop there - shops have also caught on to the fact that most of us are too lazy to stoop right down to the bottom shelf, or even stretch to the top shelf which is absurdly high. Instead, we reach for the products at a convenient height and which catch our eye because they're at eye level. Another coincidence? Of course not, shops place cheap items at the bottom and top, with the more expensive and profitable ones in the middle.

Don't think for one moment that anything a retailer does is by chance or coincidence - instead, believe all the conspiracy theories you like - they're almost certainly all true.