At the very beginning of the match there is a coin toss. The team that has won the toss, will decide if they want to bat first or field first. Each inning consists of 50 overs, and in each over there are 6 balls. For each inning it takes about 2.5-3 hrs. The team that is batting first, is pretty much trying to make the most runs possible.
Runs are runs between the wicket.
If the batsman has hit the ball past the boundary, that is 4 runs, and if he hits it outside of the field into the stadium that is 6 runs. Most runs are taken by hitting the ball slightly on the field and running between the wickets for 1 or 2 runs a ball. The fielders are the opposing team. They are trying to block the runs of the team that is batting. The fielding team also bowl to the opposing team.