Tournament Play
There are two major types of games played both online and off, one of them being tournament play. They take the form of a fixed buy in that results in a certain number of chips for the play which they have to use until they either win or lose them all. For example most sites offer blackjack tournaments in which 6 players compete for 1st and 2nd prize. The buy in can be as little as $1 so they are an excellet place to practice your play. A tournament usually has a structure in which the blinds go up by a set amount over a fixed period of time or number of hands. This is the major difference between Tournament play and sit and go.
People tend to act much more differently in a tournament setting than on sit and go tables, especially in the later stages where they tend to be more aggressive. Sometimes sites even do freeroll tournaments in which you can enter for free and still win prize money but I am yet to see this for blackjack poker.