In the trading card game, players draw cards from their respective decks and take turns playing cards onto "the field". Each player uses a deck containing forty to sixty cards, and an optional "Extra Deck" of up to fifteen cards. There are different products that come with making/building a Yu-Gi-Oh! deck. A Booster Pack is a pack of Yu-Gi-Oh! cards from one of the Booster Sets, the main sets from where new cards are released, usually every three to four months. Booster Boxes are boxes of booster packs. They will generally have 24 packs for a normal Booster Pack, 30 for a Duelist Pack and 10 for a Starter Deck, Structure Deck or Special Edition. A Structure Deck is a pre-made Deck designed to be playable straight from the box without any modification needed. It is similar to a Starter Deck, but is focused on a certain Type, Attribute, Archetype, strategy, or Yu-Gi-Oh! character.