Not Symbol ¬ Copy and Paste — Logical NOT Sign Meaning & Uses

Copy the Not Symbol Here

The logical NOT symbol ¬ is a fundamental operator in formal logic, mathematics, and computer science. Copy it right here:

• ¬ — Logical NOT / negation sign (U+00AC)
• ~ — Tilde, often used as a NOT alternative in programming
• ! — Exclamation mark, used as NOT in C-style languages
• ⌐ — Reversed NOT sign (U+2310)

Highlight the symbol you need, copy it, and paste it anywhere. The ¬ character is the standard logical NOT sign used in formal logic and mathematical notation.

What Does the NOT Symbol Mean?

The ¬ symbol represents negation — it reverses the truth value of whatever follows it. If a statement is true, ¬ makes it false. If a statement is false, ¬ makes it true. This deceptively simple operation is one of the building blocks of all digital computing and formal logic.

In plain language, ¬P reads as "not P" or "it is not the case that P." For example, if P means "it is raining," then ¬P means "it is not raining."

NOT in Formal Logic

In propositional logic and Boolean algebra, ¬ is one of the three fundamental logical operators, alongside AND (∧) and OR (∨). Together, these three operators can express any logical relationship.

The truth table for NOT is the simplest possible:

• If P is True → ¬P is False
• If P is False → ¬P is True

Double negation: ¬(¬P) = P. Applying NOT twice returns you to the original value. This principle is foundational in both classical logic and digital circuit design.

NOT in Mathematics

In mathematics, the NOT symbol appears in several contexts:

• Set theory: The complement of a set A is written as A' or ¬A — the set of all elements not in A.
• Inequalities: The symbol ≮ means "not less than," ≯ means "not greater than," and ≠ means "not equal to."
• Boolean algebra: ¬A (or Ā, an overbar) represents the complement of a Boolean variable.
• Proof by contradiction: You assume ¬P (the negation of what you want to prove) and show it leads to a contradiction.

NOT in Programming

Nearly every programming language has a NOT operator, though the symbol varies:

• ! (exclamation mark): Used in C, C++, Java, JavaScript, Python (as "not"), C#, PHP, Swift, Rust, Go, and most modern languages. Example: if (!isLoggedIn)
• not: Used as a keyword in Python, Pascal, and BASIC. Example: if not valid:
• ~ (tilde): Bitwise NOT in C, C++, Java, JavaScript, Python, and many others. Flips every bit in a binary number.
• NOT: Used in SQL for logical negation. Example: SELECT * FROM users WHERE NOT active

The ¬ symbol itself is rarely used directly in code (since keyboards do not have a dedicated key for it), but it appears in pseudocode, textbooks, algorithm explanations, and formal specifications.

Related Logical Symbols

The NOT symbol belongs to a family of logical operators:

• ∧ (AND): Logical conjunction — true only when both operands are true (U+2227)
• ∨ (OR): Logical disjunction — true when at least one operand is true (U+2228)
• ⊕ (XOR): Exclusive OR — true when exactly one operand is true (U+2295)
• → (implies): Material conditional — if P then Q (U+2192)
• ↔ (iff): Biconditional — true when both sides have the same truth value (U+2194)
• ∀ (for all): Universal quantifier (U+2200)
• ∃ (there exists): Existential quantifier (U+2203)

Copy all related symbols: ¬ ∧ ∨ ⊕ → ↔ ∀ ∃

How to Type the NOT Symbol on Keyboard

Windows

• Alt + 0172: Hold Alt, type 0172 on the numeric keypad → ¬
• Character Map: Press Windows + R, type "charmap", search "not sign"
• Word: Insert > Symbol > More Symbols > search "logical not"

Mac

• Option + L: Produces ¬ on most Mac keyboard layouts
• Character Viewer: Press Control + Command + Space, search "not sign"

iPhone and iPad

iOS does not have a ¬ key. Copy it from this page, or add a text replacement shortcut in Settings > General > Keyboard > Text Replacement. Set the phrase to ¬ and the shortcut to something like "[not]".

Android

Most Android keyboards do not include ¬ in their symbol panels. Copy it from this page for the fastest result. Alternatively, install a keyboard that supports custom symbols or use a Unicode input method.

HTML and Unicode Reference

• HTML entity: ¬ renders as ¬
• HTML decimal: ¬ renders as ¬
• HTML hex: ¬ renders as ¬
• Unicode: U+00AC, named "NOT SIGN"
• LaTeX: \neg or \lnot produces ¬

NOT Gates in Digital Electronics

In digital circuits, the NOT operation is implemented by a NOT gate(also called an inverter). It takes a single input and produces the opposite output: input 1 gives output 0, and input 0 gives output 1. The standard symbol for a NOT gate in circuit diagrams is a triangle with a small circle (bubble) at the output. Every modern computer processor contains millions of NOT gates as part of its logic circuits.

Quick Reference

All negation-related symbols for instant copying:

¬ ~ ! ⌐

From formal proofs to programming to digital circuits, the NOT operation is one of the most fundamental concepts in all of computing and logic. Bookmark this page for quick access to the NOT symbol and its relatives.