Yes buy or beware but the most classic online scam online is your online auction such as what you sometimes find on Ebay.
It pretty much takes place like this, you place your winning bid. You send your money to the auctioneer and you get nothing in return.
Then the auctioneer will threaten to leave a nasty comment on your feedback page explaining that you never paid and so on.
The second example is when the auctioneer sells a replica product at a reduce cost lets say for example your Dooney or Coach purse. After examining your winning you find out your purse is a fake.
Second is not so oblivious are information product that has no value and only sends you to a website where you can purchase this product. These products normally resell products are about 75 percent of the times junk.