This was intended as a meme but is actually a good representation of what "Null" is. In C#, when you declare string s = "My shit"; it means that "s" is a reference to a memory location that holds the data "My shit". string s = null; means that the reference "s" exists but it's not pointing to any object, as in it holds nothing. Answer from abd53 on reddit.com
Wikipedia
en.wikipedia.org › wiki › Null
Null - Wikipedia
2 weeks ago - 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.
freeCodeCamp
freecodecamp.org › news › a-quick-and-thorough-guide-to-null-what-it-is-and-how-you-should-use-it-d170cea62840
A quick and thorough guide to ‘null’: what it is, and how you should use it
June 12, 2018 - If a reference points to null, it simply means that there is no value associated with it. Technically speaking, the memory location assigned to the reference contains the value 0 (all bits at zero), or any other value that denotes null in the ...
What is Null?
This was intended as a meme but is actually a good representation of what "Null" is. In C#, when you declare string s = "My shit"; it means that "s" is a reference to a memory location that holds the data "My shit". string s = null; means that the reference "s" exists but it's not pointing to any object, as in it holds nothing. More on reddit.com
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July 5, 2024language agnostic - What is the purpose of null? - Stack Overflow
I am in a compilers class and we are tasked with creating our own language, from scratch. Currently our dilemma is whether to include a 'null' type or not. What purpose does null provide? Some of our More on stackoverflow.com
Correct me if I’m wrong, but “zero” in German is “null”. If so, how do you communicate the mathematical concept of null, meaning having no value at all?
For mathematics, do you mean the empty set? That's called "leere Menge". For computer science, it depends. Programming languages tend to be "in English" anyway, so if they have a null keyword, it's pronounced like the English word "null" most of the time, so more like "nall" would be in German. Or it's called Nullzeiger (null pointer). Some languages call it nil or None or Nothing or whatever else, which avoids the issue. Note that the null pointer tends to have the value zero anyway, so once you get to a level low enough that thinking about memory addresses makes sense, the difference disappears. I mean, I have taught programming in C to first semesters, and the difference between 0 and NULLcaused a few issues. But definitely not as many issues as the difference between 0 and '0', and that the latter is actually the number 48. But that's programming. When talking about computer science as a science (and not programming), I'm not aware of "null" being a common concept we dealt with. More on reddit.com
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February 11, 2021"Null" on everything I send from one platform to another?
I keep getting this too it's really annoying More on reddit.com
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December 21, 2024Videos
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What does null! even mean - YouTube
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Null | meaning of Null - YouTube
What is null? @khalidwarsa #null #programming #programmingconcept #tech #techjob #selftaught #selftaughtdev #flutter #typescript #dart #nothing #nullcase | TikTok
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What exactly is NULL? - YouTube
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What is NULL RESULT? What does NULL RESULT mean? NULL RESULT meaning, ...
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Null Meaning - YouTube
MDN Web Docs
developer.mozilla.org › en-US › docs › Glossary › Null
Null - Glossary - MDN Web Docs
In computer science, a null value represents a reference that points, generally intentionally, to a nonexistent or invalid object or address. The meaning of a null reference varies among language implementations.
TechTerms
techterms.com › definition › null
Null Definition - What does null mean to a computer?
September 26, 2022 - Null, in computing terms, refers to the absence of a value. It does not mean a value of 0, since 0 is itself a value, nor does it mean a blank space " ".
ThoughtCo
thoughtco.com › definition-of-null-958118
What Does Null Mean in C, C++ and C#?
April 27, 2019 - Null is a constant built into C, C++, and C#. It has a value of zero. Null can also be the value of a pointer that points nowhere.
Reddit
reddit.com › r/learnprogramming › what is null?
r/learnprogramming on Reddit: What is Null?
July 5, 2024 -
So I use C# and I often see many devs use null.
What and which kind of situation do you use this variable?
I am reading c# guide on programming book and I am on Clearing memory now and I haven't encountered null yet. Should I be worried?
Top answer 1 of 18
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This was intended as a meme but is actually a good representation of what "Null" is. In C#, when you declare string s = "My shit"; it means that "s" is a reference to a memory location that holds the data "My shit". string s = null; means that the reference "s" exists but it's not pointing to any object, as in it holds nothing.
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NULL is nothing. It means theres nothing there. Often its just a place holder before something is there. Say u have a bunch of variables of animals. U might set them to NULL before u know what they are. Then u might check if they are NULL before u add an animal to them. Things are initialized as NULL.
PCMAG
pcmag.com › home › encyclopedia › n
Definition of null - Encyclopedia
In hex, it displays and prints as 00; in decimal, it may appear as a single zero in a chart of codes, but displays and prints as a blank space. Nulls are naturally found in binary numbers when a byte contains all zeros, and they are used to pad fields (see padding).
Khoury College of Computer Sciences
khoury.northeastern.edu › home › kenb › MeaningOfNull.html
The Meaning of Null in Databases and Programming Languages
For the rest of this article, I will use the convention that "NULL" (all uppercase letters) means "database null" and "null" (all lowercase letters) means "programming language null". One consequence of defining NULL differently from null is that one cannot use ordinary Boolean logic. The result of a logical expression now has three possible values rather than just two. In addition to TRUE and FALSE, one must now admit the possibility of NULL.
Computer Hope
computerhope.com › jargon › n › null.htm
What Is Null?
April 26, 2017 - Null defines a lack of value. For example, in the example below, the $value1 variable is null and $value2 has a value of 1.
Quora
quora.com › What-does-NULL-mean-in-programming-languages
What does NULL mean in programming languages? - Quora
Answer (1 of 6): null is the pointer or reference to address zero. Why would this be needed or used? Let’s say you are searching for a library book that you want to read. Unlike Amazon, your library doesn’t have every book.
HowtoForge
howtoforge.com › home › what does null mean in linux and computing
What does null mean in Linux and Computing
In this article, I will give you a short explanation of what the value null or the null device means in the computing world. The value null basically means that a variable has no value.
Medium
medium.com › @sumeet2703 › understanding-the-difference-between-zero-and-null-in-programming-db60b4e12934
Understanding the Difference Between Zero and Null in Programming | by Sumeet K | Medium
September 4, 2024 - No Value: Null indicates that a variable doesn't point to any object or value in memory. Memory: Assigning null to a variable typically means that no memory is allocated for it beyond the pointer or reference itself.
TechCareer
techcareer.net › en › dictionary › null
What is Null? What does it do?
Null, in many programming languages, means "empty" or "nothing." It is used to indicate that a variable has no value. Null shows that an object or reference does not contain any data or does not point to an object.
Medium
medium.com › @shlomohassid › null-how-do-you-define-nothing-and-why-would-you-07683bdbe63a
NULL: How Do You Define Nothing? And Why Would You? | by Momi | Medium
May 31, 2025 - There’s no magic “null” in hardware — just the number zero, which we’ve collectively agreed means “points to nothing.” And that choice of zero isn’t a fluke either — there’s a very practical reason why address zero was chosen.
Quora
quora.com › What-is-the-definition-of-null-in-computer-science-Why-is-it-considered-as-a-special-value-or-state-for-variables-and-arrays
What is the definition of 'null' in computer science? Why is it considered as a special value or state for variables and arrays? - Quora
NULL generally is the value given to something that is “missing”. For example, in databases a value could be a boolean (TRUE or FALSE) but if the value was missing or unknown, we might also allow NULL.
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Null: The Billion Dollar Mistake. Tony Hoare:
I call it my billion-dollar mistake. It was the invention of the null reference in 1965. At that time, I was designing the first comprehensive type system for references in an object oriented language (ALGOL W). My goal was to ensure that all use of references should be absolutely safe, with checking performed automatically by the compiler. But I couldn't resist the temptation to put in a null reference, simply because it was so easy to implement. This has led to innumerable errors, vulnerabilities, and system crashes, which have probably caused a billion dollars of pain and damage in the last forty years. In recent years, a number of program analysers like PREfix and PREfast in Microsoft have been used to check references, and give warnings if there is a risk they may be non-null. More recent programming languages like Spec# have introduced declarations for non-null references. This is the solution, which I rejected in 1965.
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null is a sentinel value that is not an integer, not a string, not a boolean - not anything really, except something to hold and be a "not there" value. Don't treat it as or expect it to be a 0, or an empty string or an empty list. Those are all valid values and can be geniunely valid values in many circumstances - the idea of a null instead means there is no value there.
Perhaps it's a little bit like a function throwing an exception instead of returning a value. Except instead of manufacturing and returning an ordinary value with a special meaning, it returns a special value that already has a special meaning. If a language expects you to work with null, then you can't really ignore it.
Wikipedia
en.wikipedia.org › wiki › Null_(SQL)
Null (SQL) - Wikipedia
19 hours ago - A parameter after the first non-NULL parameter could be a function, which could either be computationally expensive, invalid, or could create unexpected side effects. The NULL literal is untyped in SQL, meaning that it is not designated as an integer, character, or any other specific data type.
HistoryNull propagationComparisons with NULL and the three-valued logic (3VL)Analysis of SQL Null missing-value semanticsCheck constraints and foreign keysOuter joinsAggregate functionsWhen two nulls are equal: grouping, sorting, and some set operationsEffect on index operationNull-handling functionsData typing of Null and UnknownBOOLEAN data typeControversyFurther reading
Medium
medium.com › @alessandromordini › the-philosophical-implications-of-null-in-computer-programming-aac059e7b3d
The Philosophical Implications of NULL in Computer Programming | by Alessandro Mordini | Medium
February 4, 2023 - The concept of “NULL” in coding is a crucial one, with far-reaching philosophical implications. NULL represents the absence of a value in…
Kotobas
kotobas.net › en › what-is-null
What is Null? - A Concise Explanation of Its Meaning and Concept - KOTOBAS
March 16, 2025 - In the realms of programming and computer science, Null signifies a state of “nothingness” or an absence of data. Null indicates a state where nothing exists or no valid value is assigned.
Merriam-Webster
merriam-webster.com › dictionary › null
NULL Definition & Meaning - Merriam-Webster
1 month ago - The meaning of NULL is having no legal or binding force : invalid. How to use null in a sentence. Did you know?