Null symbol
Null symbol may refer to:
- Null character, U+0000 <control-0000> , U+2400 ␀ SYMBOL FOR NULL (a single-character glyph "NUL")
- Null sign (∅), the empty set
- Null (SQL) (ω), a special marker and keyword
NULLin SQL - Empty string (λ, Λ, or ε), in formal language theory