Shutting Down

Shutting down is a term used when your opponent cannot use certain cards to maintain field advantage or effects that do not let them use their Spell & Trap Card Zone.

Examples
The Ojama cards are good examples of material that can shut down the opponent's field. If you are looking for a shut down deck, one of the best would be an Ojama deck, focusing on getting out Ojama King or Ojama Knight. If you can get both of these cards on the field at the same time, your opponent cannot even Summon a monster!

Other cards that can also shut down your opponent can be cards like: Xing Zhen Hu Ground Collapse Or even cards that Summon tokens to your opponent's side of the field, if you can get 5 to their side, they have no way to Summon monsters.