You will win or share (in the case of multiple winners) the jackpot prize of the pool.
You can also win or share (in the case of multiple winners) a consolation prize for a near miss by one or more selections. You can see the consolation prize(s) available for a pool by clicking on “More info” in the pool header.
Remember that if you chose a lower than the default (‘fractional’) stake when you placed your bet, you are now playing for the equivalent fraction of the full jackpot and consolation prizes. You can remind yourself of the prize (full or fractional) you are playing for by looking at your ticket under "My tickets".
Read more about tracking the progress of your tickets here.