BitFinex is a bitcoin to fiat exchange, a margin trading exchange, and a liquidity provider. The platform offers a number of features that expand the financial positions you can take - for example the ability to short Bitcoin via margin trading.
The exchange also offers a set of other cryptos apart from bitcoin such as Litecoin and Ethereum.
Deposits and withdrawals take place via the standard bank transfer means with fees of 0.1% and a minimum of $20. Bitcoin and Litecoin are free.
BitFinex takes security seriously and have moved from a hot wallet cold wallet set up to segregating customer funds where each user has access to their own wallet which they can review on the blockchain.
Bitfinex was hacked on 03 August 2016 and around 120,000 BTC were stolen.
Fee of 0.1% for most trades

Coinbase is one of the most prominent and influential crytpo companies. It is the most recognizable exchange in the United States and has over 20 million users worldwide.It is extremely user-friendly and is great for beginners. Coinbase is the intro platform for many first time crypto investors because it has a number of features such a free GDAX account for all users, a user friendly mobile App,  and built in wallet options.
There are a variety of security measures, and all funds are insured by the FDIC up to $250,000. Because of this, Coinbase is a very secure and reliable exchange with a reputable brand name
Its' clean and simple platform make it easy to quickly buy or sell cryptocurrency, and track funds through individual currency wallets.
Coinbase is a fully regulated exchange that is compliant with all laws, and because of their size and brand, they have been the subject of IRS investigations in which they were forced to disclose trading information for thousands of user accounts. They openly track user details and trading information. and have been known to close accounts for violating the terms and conditions.This is one of the main reasons that some traders prefer to use another exchange when they have become more familiar with the crypto ecosystem.
Coinbase also has  a relatively small amount of currency pairings and the platform does not have tools to accommodate more advance technical traders.
Coinbase also offers a variety of funding methods that make it an attractive choice for US residents that want to start buying crptocurrencies.Accounts can be easily funded. Since Coinbase is regulated, US bank accounts can be directly linked. This allows for relatively easy deposits and withdrawals, with a flat fee of 1.5% for buying via a US account. The trading fee is 0.25%

Bitstamp is one of the most popular fiat to Bitcoin exchanges. It was one of the first big exchanges and it provides customers with a platform that is secure and easy to use. It was originally started in Slovenia but has moved its' operations to Luxembourg.
Bitstamp uses MultiSignature technology for its hot-wallet, as well as a fully insured cold-storage option where kept off-line. They also offer a number of other security features such as two-factor authentication and confirmation emails to enhance account security.
Bitstamp provides the option for limit orders, stop loss, and trailing stop orders. They have an easy to use API that can be integrated into user applications. T
Overall, Bitstamp is a secure and reliable exchange with good liquidity and a solid infrastructure. It is a good option for beginning traders as well as more advanced crypto holders.
Trading Fees: Tiered system depending on volume ranging from 0.1%-025%