Editing Null (section)

==Science, technology, and mathematics==
===Astronomy===
*[[Nuller]], an optical tool using interferometry to block certain sources of light
===Computing===
*[[Null (SQL)]] (or NULL), a special marker and keyword in SQL indicating that a data value does not exist, is not known, or is missing.
*[[Null character]], the zero-valued ASCII character, also designated by {{mono|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 <code>/dev/null</code>
*[[Null pointer]] or reference (sometimes written <code>NULL</code>, <code>nil</code>, or <code>None</code>), an object pointer (or reference) not currently set to point (or refer) to a valid object

===Mathematics===
*[[Null (mathematics)]], a zero value in several branches of mathematics

===Physics===
*[[Null (physics)]], a point in a field where the field quantity is zero
*[[Null (radio)]], a concept in electromagnetism