Wii Remote
"Wii Sports" and "Wii Sports Resort" support up to four players. The Wii Remote acts as the main controller for each game. You need one Wii Remote in order to play single-player games. Certain multiplayer games, such as tennis, require each additional player to have her own Wii Remote. Other multiplayer games, such as bowling, require only one controller, with each player taking a separate turn.
Wii Nunchuk
The Wii Nunchuk is a secondary controller that attaches to the main Wii Remote. It is not required for many games in "Wii Sports." However, you need one to play a single-player round of boxing or two for multiplayer boxing. In "Wii Sports Resort," the archery, cycling and powercruising games require the use of the nunchuk, while the remaining games can function without it.
Wii MotionPlus
The Wii MotionPlus attachment is not required when playing "Wii Sports," but it is essential when playing "Wii Sports Resort." The Wii MotionPlus attachment provides extra precision when using the Wii Remote, making player input more accurate and reliable. You will need a Wii MotionPlus attachment for every Wii Remote that you intend to use while playing Wii Sports Resort. Some retails provide the option of buying the game by itself or bundled with a Wii MotionPlus accessory (correct as of June 2013).
Nintendo Wii Sports Pack
You can purchase additional accessories to attach to your Wii Remote to make the game feel more lifelike. These accessories include tennis racket, baseball bat and golf club extensions. They're purely for aesthetic purposes and are not required to play the game. An 8-in-1 Sports Pack for "Wii Sports Resort" is available for purchase.