Null may refer to:

Science, technology, and mathematics edit

Astronomy edit

  • Nuller, an optical tool using interferometry to block certain sources of light

Computing edit

  • Null (SQL) (or NULL), a special marker and keyword in SQL indicating that something has no value
  • Null character, the zero-valued ASCII character, also designated by NUL, often used as a terminator, separator or filler. This symbol has no visual representation.
  • Null device, a virtual file that discards data written to it, on Unix systems /dev/null
  • Null pointer or reference (sometimes written NULL, nil, or None), an object pointer (or reference) not currently set to point (or refer) to a valid object

Mathematics edit

Physics edit

Arts and media edit

People with the surname edit

See also edit