Call a raise from an early position raiser only with very good hands.
A raise from a classic poker player in early position would nearly always indicate a hand of great 
strength. Consequently, you would have to bump up your playing standards significantly. One of your goals in holdem poker must be to try to enter pots with what you think would be the best hand as often as possible. Calling early-position raises with a wide range of hands would not be the way to achieve this aim.
What poker hands would be playable against an early-position raise? In the absence of other callers, if you were to stick to a very selective approach of playing only an ace and queen suited, an ace and king, or a pair of jacks or better, you would avoid putting your money in with the worst hand too often.
At first glance, it would appear that a pair of tens would be a good holdem poker hand. And it would be. But when the first poker player in were to have raised the pot, you would have to ask yourself, ‘What range of hands would he be likely to be holding in this situation?’ If the raiser was a solid poker player, you should toss that pair of tens into the muck.
The reason for this would be that most solid players would raise up front with only a few hands: a pair of aces, a pair of kings, a pair of queens, a pair of jacks, a pair of tens, an ace and king and an ace and queen. Your pair of tens would be a major underdog if your rival were to have a pair, and only a slight favorite against an ace and king or an ace and queen.
It would be important to avoid these types of either-or situations in holdem poker as much as possible, if you were planning on winning at the game. Either you would be a big underdog or you would be a slight favorite.
Nonetheless, if the early-position raiser were a loose or wild player, you would be playing too tightly if you were to fold your tens. Encyclopedia of Game ! The reason would be that a maniac would raise the pot with a huge number of hands that would be dominated* by your two tens, inclusive of smaller pairs. An ace and x, or even hands such as a seven and eight suited. Against this type of rival, the correct play would be to re-raise in an effort to play your pair heads up against the maniac.
*Dominated: The situation in holdem poker of one hand being considerably ahead of the other, often because of having the same card in common plus a higher card. For instance, any higher pair would dominate a king and queen offsuit.
When a player raise from late position you should reraise from the small blind.
There would be numerous reasons why playing your hand this way would be proper, all of which would 
center around the basic truth that poker players would open-raise from the late position with less than-premium hands. After all, you would do this yourself.
What sorts of hands might you re-raise with from the small blind ? Against a raise from the button (unless he were to be a straight poker player), you could re-raise in the small blind with hands as weak as an ace and eight offsuit, any pair, or a king and jack offsuit.
For one thing, it would be quite possible that you would be holding the best poker hand here. Your rival on the button might have a hand like a queen and ten, an ace and three, or a ten and eight suited. It would never be a bad thing to get more money into the pot when you were to have the best hand.
Also, by re-raising, you would most likely cause your rival to read you for more strength than you would actually have. This could be useful later in the hand, which would enable you to steal the pot on the flop or turn with a bet if the board would be of no help to your rival. What you would have done would be to take the lead in the hand. Winning holdem poker players would play aggressively helping themselves to the large number of pots that would be there for the taking.
For another, the big blind would often call one raise, but not two. Usually, you would like to raise this poker player out if were to have the opportunity, and would send his blind money to the center of the pot. This would create a bit more value on your hand, with the existence of some dead money* in the pot. You would principally have to lean towards re-raising a late position raise if the big blind was to be a good poker player, as you wouldn’t need him in your pot anyway.
One further advantage of re-raising regularly from the small blind against a steal position** raiser would be the psychological effect it would have on your poker rivals. They would finally tire of your aggressive play, and think twice before raising when you would be in the blinds. This might allow you to see more cheap flops than you would be entitled to; a nice perk would be produced by your aggressive play.
*Dead money: Previous bets forsaken in the pot such that the poker players who had made those bets, having folded, couldn’t win the pot. Dead money would include folded blinds.
**Steal position: In a game with blinds, a late position, often the cutoff (position one to the right of the button) or button; so used because it would be most likely from this position that a poker player would effort to steal the blinds, that is, open with a raise in the hope of not getting called by either blind.