A game is made up of 10 ends (like innings). An end consists of each team member shooting (delivering)
  two rocks, or stones, alternately with the opponent's. When all 16 rocks have been delivered, the score for
  that end is determined.
 
      A 12-foot circle (the "house") is the scoring area. For each stone closer to the center of the circles (the tee)
  than any of the opponent's, one point is scored. The team scoring shoots first in the next end, giving the
  opponent the "hammer," or last shot of that end. Teams will sometimes give up a point or two to secure the
  next end's hammer.
 
      The sheet of ice (playing surface) is 15' 7 1/2" wide and 146 feet long, set up to accommodate play in both
  directions. Most curling takes place in curling clubs, which commonly have two to six sheets of ice.
  Hockey arenas are also used as temporary curling rinks; they accommodate six sheets.
 
      All four players shoot two rocks, beginning with the player referred to as the "lead." The "second" shoots
  next, and then the "third," or "vice skip." The skip usually shoots the last rocks, and directs the play of the
  others.
 
      The skip decides on shot selection, and "reads" the curl in the ice for the shooter. The shooter must be
  accurate in three functions:
 
      1.Aim (at the broom) 2."Weight" (velocity imparted to the stone) 3.Imparting the correct "handle" (curl) to
  each shot
 
 
 
      Shots are called either to stop at a certain point on the sheet ("draws" or "guards") or to have enough
  weight to strike another rock out of play ("take-outs" or "hit and rolls").
 
      Each running stone curls, or curves, as it proceeds down the ice based on the twist given it during the
  delivery. The amount of curl varies based on the ice surface and the speed of the rock. The curl allows for
  better control of the stone and also provides a means to shoot around guards.
 
      Sweeping-with either a straw broom, hogs hair or horse hair brush, or synthetic brush adds the element of
  fitness to curling because, to be effective, sweeping must be very vigorous. Sweeping slightly melts the ice,
  which reduces the friction between the running stone and the ice. The result is that the stone will curl less,
  and slide further.
 
      Sweeping is called for when the stone has not been delivered firmly enough, and/or when the shot is aimed
  "narrow," or inside the broom target. Sweeping can help a rock slide up to an additional 15 feet. Top teams
  control most shots by using aim and weight "within the sweeping zone."
 
      Strategy is a major part of curling. Shots are played with an eye to the last rocks of each end, not simply
  placed at the center of the circles. The strategy can be rather complex. Innovations are constantly being
  made and adopted when the innovators win, similar to other sports where strategy and the game plan plays
  a major role.
 
      It is common for games between national-class teams to be very close, with both skips jockeying for the
  last shot in the last end. Here, the mental toughness factor is crucial to success.