PokerStars is the largest poker room in the world. The site offers great promotions and is a leader in cash games and tournaments.
The game variety of PokerStars is good; the software has great functionality with fast play and decent graphics.
This poker room still accepts U.S. players and has some great customer support.

PokerStars received good publicity after the performance of some of its players at the World Series of Poker, for instance, Chris Moneymaker, Greg Raymer and Joe Hachem won the World Series of Poker Main Event back to back to back.

There is a massive traffic in all the games, including Limit and No Limit Texas Hold'em, Omaha Hi, Omaha Hi/Lo, No Limit Omaha Hi/Lo, Seven Card Stud Hi, Seven Card Stud Hi/Lo, H.O.R.S.E., H.O.S.E., and Razz, among others.

Full-table games are available, as well as short-handed and heads-up tables. There is no rake when you play at the micro-limit tables.
This poker room hosts a ton of tournaments and freerolls; the high traffic ensures that players looking for a tournament will most likely find what they are looking for.

The site runs plenty of satellite tournaments to the World Series of Poker and other major live and online poker events. Every Sunday, PokerStars runs a huge Million Dollar Guaranteed tournament! The heavy concentration of players guarantees loose and juicy smaller buy-in tournaments, though most of the tournaments that run often have low to medium buy-ins.

There are also plenty of $500 or more buy-in tournaments available for the high-stakes players. Overall, PokerStars offer massive player volume, game diversity and software quality plus generous promotions and bonuses for loyal players.  The software is available for both MAC and PC users and is updated frequently to ensure safety and stability, with virtually no downtime as a result.