The point of the game is to score as much as possible. Fast play is favored.
By dropping figures (with space) one can get many points - score for droping is proportional to the number of lines the figure falls. Speed increases with time and not with score.
To restart just press F5. To pause press Pause/Break button or P.
To control block's position use left and right buttons, a and d or h and l. To rotate figure press up button, w or j. Ctrl+up or Shift+w(j) rotates clockwise.
To lower figure by one level press down arrow, s or k. It is recommended though to drop figures with space as it's faster and yields significant amount of score.