Bitstamp is a European bitcoin exchange that has been running continuously since 2011. Its reputation has also made it one of the most common places to buy bitcoins on the internet. They accept U.S. Dollars and European Euros, as well as British Pounds and Swiss Francs.
Bitstamp's fee schedule is not very complicated. Bitstamp collects a small fee on every transaction based on the exchange volume, calculated in U.S. dollars. For transactions under $20,000, the fee is 0.25 percent. At $100,000, the fee drops to 0.24 percent and then continues to drop roughly every time the transaction amount doubles until it bottoms out at 0.10 percent at the $20 million mark. Not only is this system simple to understand, it incentivizes bulk purchases, which makes it simpler for large financial institutions to move in and out of the currency. Bitstamp also recently lowered its wire transfer fees, which is a nice bonus.
As far as security goes, Bitstamp keeps things pretty basic. It offers two-factor authentication that tethers a user's account to a phone or other device, as well as a password, to protect your account from hijacking. Bitstamp also commits to preventing money laundering and other shady financial practices on its network. As with most bitcoin exchanges, Bitstamp doesn't let anyone buy bitcoins with their PayPal balance, to prevent scammers from reversing PayPal transactions to collect bitcoins for free.
Bitstamp also offers a simple and well-documented API, explaining it on a single page of the company's site. The API has a 600 request per 10-minute limit to prevent overtaxing the network and does not make specific allowances for margin trading, as that runs counter to the exchange's philosophy. It does, however, give you total access to your private account, with specialized methods for trading in both bitcoin and Ripple, as well as a quick way to pull up and analyze the public order book and ticket information.
Overall, Bitstamp is not the most innovative network, and it does not have highly advanced security techniques. However, it has a large trading volume and trades in a number of different currencies.