How essential is poker tracking software for online play

I'm trying to get into playing poker more seriously online and know that many good players use poker tracker to record data about their games. I am wondering if I should continue playing online without this type of software, how disadvantaged am I, could I be learning at a much faster rate with the software instead of without.

Thank you

There's nothing more critical imho. The ability to track your hands, stats, run filters, review and analyze your play... it's the best tool for improving bar none.

There's more options out there now, so try them and see what you like. I'm obviously a Drivehud fan. http://drivehud.com