Scorecards are full of numbers. Here is what the main ones mean.
Batting
Average is runs scored divided by the number of times the batter has been dismissed. Not-out innings add runs but not dismissals, which is why averages can climb quickly.
Strike rate is runs per 100 balls faced. A batter who makes 50 off 25 balls has a strike rate of 200. It matters most in T20s.
Bowling
Economy rate is runs conceded per over. In T20s, anything around seven is considered good.
Bowling average is runs conceded per wicket, and bowling strike rate is balls bowled per wicket. Lower is better for both.
A maiden is an over in which the bowler concedes no runs. Byes and leg byes do not count against the bowler, so an over can still be a maiden if they are scored.