--- aliases: [empty set, null set] --- #sets-functions ## Definition > [!tldr] Definition > The **empty set** or **null set** is the [[Set|set]] that has no elements in it. We denote the empty set $\emptyset$. Notes: - The empty set is a [[Subset|subset]] of every set (including itself) because of the way [[Conditional statements]] are used in the definition of "subset".