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. Answer from Draegan88 on reddit.com
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?
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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.
Where do NULL values come from in datasets and how to handle them? Jun 8, 2024
r/learnprogramming 2y ago
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 - Note: Some programming languages (mostly functional programming languages like Haskell) don’t support the concept of null. Instead, they use the Maybe/Optional Pattern to represent the ‘absence of a value’. The compiler ensures that the ‘no value’ case is handled explicitly. Hence, null pointer errors cannot occur. ... If a reference points to null, it always means that there is no value associated with it.
language 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
What is Null?
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. More on reddit.com
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July 5, 2024What does “null” mean and why is it here
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March 21, 2023What does 'null' mean in this piece of code?
Here it is just so that the variable "out" is set to something instead of being "uninitialized". Usually used in the finally block then you want to close it. and you cant access variables from inside the try block.
More on reddit.com 6
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December 29, 201402:30
What Is "Null" In Programming? - Learn To Troubleshoot - YouTube
18:06
What exactly is NULL? - YouTube
03:28
Definition: What is a Null Value? - YouTube
15:22
Nulls and null checks - How to work safely with nulls in any codebase ...
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What Does Null Mean? - Intro to Java Programming - 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.
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.
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. If you search for “Object Oriented Software Construction” by ...
TechTerms
techterms.com › definition › null
Null Definition - What does null mean to a computer?
September 26, 2022 - It does not mean a value of 0, since 0 is itself a value, nor does it mean a blank space " ". It also does not refer to an undefined variable, which has not been created at all. In the context of programming languages, a variable that has no value assigned is considered null.
Khoury College of Computer Sciences
khoury.northeastern.edu › home › kenb › MeaningOfNull.html
The Meaning of Null in Databases and Programming Languages
The main distinction between the relational null and the programming language null is the following: The relational null represents the absence of a value in a field of a record; whereas the programming language null represents one of the possible values of a variable.
Microsoft Learn
learn.microsoft.com › en-us › dotnet › csharp › language-reference › keywords › null
null keyword - C# reference | Microsoft Learn
null is the default value of reference-type variables.
TechCareer
techcareer.net › en › dictionary › null
What is Null? What does it do?
Null plays an important role in various programming languages and is a fundamental concept that software developers need to understand. Null, in many programming languages, means "empty" or "nothing."
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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.
DevX
devx.com › home › null
Null - DevX
January 17, 2024 - In programming languages such as JavaScript, C, and Java, a null value can be assigned to variables to indicate that they do not have a valid object reference or lack any value or data.
Medium
robertdelwood.medium.com › thinking-like-a-programmer-understanding-null-959a5da1d625
Thinking Like a Programmer: Understanding Null | by Robert Delwood | Medium
September 21, 2025 - With null, there is now a third condition. A null binary commonly means that information does not always have to be available or is not applicable. Some API developers do not even return a field if it’s null.
Zenva
gamedevacademy.org › home › software development › what is null in programming – complete guide
What Is Null In Programming - Complete Guide - GameDev Academy
November 21, 2023 - ... In programming, ‘null’ represents a null reference or a null pointer, which essentially means “no object” or “no value here”. It is a placeholder that signifies the absence of a value or a non-existent object.
Oreate AI
oreateai.com › blog › understanding-the-meaning-of-null-in-technology-and-everyday-life › fcb099fcbe694734007ed2e6f15b837f
Understanding the Meaning of 'Null' in Technology and Everyday Life - Oreate AI Blog
December 30, 2025 - 'Null' represents absence across technology and daily life—from programming errors to legal terminology signifying invalidity.
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.
Coderanch
coderanch.com › t › 688734 › java › null
what does null mean? (Beginning Java forum at Coderanch)
December 24, 2017 - Alyxandra Harp wrote:From my understanding of null, it means the variable has no value. It is not any number, not even 0. A null value is for reference variables only. If a reference variable has a value of null, it means that it is not referring to any object/instance.
Wikipedia
en.wikipedia.org › wiki › Null
Null - Wikipedia
June 20, 2026 - 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 NUL, often used as a terminator, separator or filler.
CodeItBro
codeitbro.com › home › glossaries › coding glossary › null
What is Null in Programming? Detailed Explaination
May 18, 2025 - Null is a special value in computer science that represents the absence of a valid value or object reference, serving as a placeholder to indicate that a variable, pointer, or reference does not currently point to any meaningful data or memory ...
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 - Null, on the other hand, represents the absence of a value or a reference. It is not a number, nor is it a default value—it signifies that a variable has not been assigned any value at all.
Medium
medium.com › @andrecalil › what-does-null-mean-008cfd7cf5f8
What does NULL mean?. The concept of a null something exists… | by Andre Calil | Medium
August 2, 2024 - Typically the meaning of a null property relies on previous knowledge. The team involved in that decision might carry that experience, but not newcomers. The null condition of a property isn't clearly named, which deepens the complexity of understanding the hidden meaning.