Null symbol

Null symbol may refer to:

• Null character, U+0000, U+2400 "symbol for null" (␀), a single-character glyph "NUL"
• Null sign (∅), the empty set
• Null (SQL) (ω), a special marker and keyword NULL in SQL
• Empty string (λ, Λ, or ε), in formal language theory

Look up null or ␀ in Wiktionary, the free dictionary.