One of the most important aspects of poker is knowing what cards are worthwhile to play, and which should be folded right away. Playing the right starting hands in the right situations increases the odds of winning exponentially.
The starting hand charts provided here are great tools to use in determining play based on your hole cards. Each possible starting hand is listed in every possible position and pre-flop situation in order for you to see what the best course of action is in any possible situation.
When you are staring out, it is a great tool to keep open while playing online poker, and will guide you towards making the best and most profitable decisions.
After a while, you will learn how to adjust your style and not play strictly by the chart, while still abiding by the general guidelines of good starting hands.
On a table with unusually tight players, you may want to be a little more aggressive with raises in the middle and late positions, despite what the chart says. Likewise, with very aggressive players, it is a good idea to wait for great cards and play more conservatively than the chart indicates.