There are many tactics that players use to grasp the hands of the other players. If you are playing at the land based casino, you can study the body language of the players as well as the dealer to determine the type of cards they are holding. For example, if the dealer got a image card, he just glances at it and if it is anything between A to 10, he takes it a little higher to read the card properly.
If a person takes too long before he or she bets, it means the player has a good hand. People with a good hand often think a lot whether to bet more or keep the same bet. Many players just go on betting without thinking anything. There are two categories of people who act like this. Either the player is a newcomer or he has a winning hand. Others go around telling players about the hands they have. They may be bluffing or just talking out in frustration. You have to do careful analysis in such cases. These are some tells in the online poker.
Many other professionals have proven that these are not just baits, though they can be used as baits. You may follow the strategies described above to understand the situation of the table and thereby decide your bets.