When you're out shopping with your mates it's always good to bag a bargain.
But are you always getting the genuine article?
Across Europe there's been a big increase in the number of fake goods for sale.
Newsround's Ricky's been investigating...
I spent the day at Quality House in London, home to the Trading Standards investigators.
Can you spot the difference?
It's their job to make sure shops are selling genuine goods, like T-shirts, DVDs, toys and loads of other stuff you find in your local shopping centre.
They have the power to prosecute shop owners and stall vendors who are selling fakes.
Inside the building were two large rooms filled to the brim with fake stuff that had been taken away by the Trading Standards on raids across the south of England.
Tips for spotting a fake:
Really low prices should get your alarm bells ringing;
The logo might be off centre or slightly different to the genuine article;
Fake trainers and clothes usually have loose threads;
Colours might bleed into each other or it might not be consistent throughout;
Look out for poor quality zips and laces.
Lots of the fakes were disguised as designer labels like Levis, Nike and Adidas.
The fakes end up being sold for a lot less money, but it's you guys who fall victim to the dodgy merchandise.
The fake clothes, toys and trainers are not only illegal, but they're also really bad quality.
Some of the fake clothes fall apart after a couple of washes, and lots of the toys haven't passed the necessary safety requirements.
As part of our Newsround investigation, the Trading Standards gave me some fake trainers, batteries, designer bags and sweatshirts.
I took them all along to a school to see if the students there could spot the difference between the imitations and the real deal.
Loads of the kids couldn't tell the difference, which proves just how hard it is to spot a fake.