The beauty of online poker is that it allows players to use (quite legally) several tools to help them at the tables when they are making decisions. One of the most powerful tools is undoubtedly the tracker. The tracker will have 2 functions: record all lost poker hands as text files and display this information in real time at the poker tables. I don't use the tracker, but I know that there are players who use the tracker. The beauty of the tracker is that it also has a Heads-Up Display (commonly known as a HUD) that will display player information stored in the database in real time.
If you play online, a poker database / tracker is a must. If you're not playing with one for some random bad reason, you're missing out for many reasons.
1) Just tracking all of your play alone is SO important to grow as a poker player.
2) The ability to analyze your game, run filters, look and replay hands is key to becoming better.
3) Understanding how to get into advanced meta game play w/ other regulars will improve your game.
I've learned over the years that there are some people who are intimidated by them (I guess they feel overwhelmed), and hence they hate of them. There's some that feign faux integrity claims (this is silly since most sites allow HUDs, as they should), and then there's people that dig in and do the work. <--- these people tend to be winners in poker and life for the exact same reasons.
Drivehud 2 has a free 30 day trial. Drivehud is a long time supporter of cardschat, so any time you have questions, there's localized support here to help as well.