If all the players besides the blind payers call, the person who paid the little blind will only need to pay the other half the blind to match the ante. Once the blinds are paid and the cards examined, players then decide whether they want to call (match the big blind, which is the starting ante or minimum requirement to play), raise (increase the ante), or fold (simply quit for the round).
The big blind's value is also the minimum betting amount for all betting rounds until the blinds increase. The blinds at the start of the tournament are $100 for the first (little) blind and $200 for the second (big) blind. Two cards are dealt to each player, and the two players to the left of the one with the dealer chip pay the blinds, which are to ensure that the pot actually has some money to begin with.
Someone is given the dealer chip, which determines who will pay the blinds for that round.