https://math.stackexchange.com/questions/864606/difference-between-%E2%89%88-%E2%89%83-and-%E2%89%85
$\approx$ is used mostly for the approximate (read: calculated) value of a mathematical expression like $\pi \approx 3.14$ In LaTeX it is coded as \approx. $\cong$ is used to show a congruency between two mathematical expressions, which could be geometrical, topological, and when using modulo arithmetic you can get different numbers that are congruent, e.g., $5 \text{ mod } 3 \cong 11 \text

https://en.wikipedia.org/wiki/Glossary_of_mathematical_symbols
A mathematical symbol is a figure or a combination of figures that is used to represent a mathematical object, an action on mathematical objects, a relation between mathematical objects, or for structuring the other symbols that occur in a formula. As formulas are entirely constituted with symbols of various types, many symbols are needed for

https://www.mathsisfun.com/symbols.html
Symbols save time and space when writing. Here are the most common mathematical symbols:

https://en.wikipedia.org/wiki/Multiplication_sign
The multiplication sign (×), also known as the times sign or the dimension sign, is a mathematical symbol used to denote the operation of multiplication, which results in a product. While similar to a lowercase X (x), the form is properly a four-fold rotationally symmetric saltire.. The symbol is also used in botany, in botanical hybrid names and the Heavy Goods Vehicle industry, to calculate

https://www.mathematics-monster.com/symbols/Dot-Operator.html
The Dot Operator, symbolized as ⋅ is a mathematical notation frequently employed in various mathematical contexts. One of its primary usages is in vector calculus, where it represents the dot product. Additionally, it can denote multiplication in some scenarios, especially when traditional multiplication signs might be confusing.

https://wumbo.net/symbols/dot-operator/
The dot operator symbol is used in math to represent multiplication and, in the context of linear algebra, as the dot product operator. Typically, the symbol is used in an expression like this: 3⋅ 5. In plain language, this expression means three multiplied by five. The interpunct symbol also referred to as the middle dot, dot product symbol

https://www.wikiwand.com/en/List_of_typographical_symbols_and_punctuation_marks
Typographical symbols and punctuation marks are marks and symbols used in typography with a variety of purposes such as to help with legibility and accessibility, or to identify special cases. This list gives those most commonly encountered with Latin script. For a far more comprehensive list of symbols and signs, see List of Unicode characters. For other languages and symbol sets, see below

https://emojipedia.org/warning
A triangle with an exclamation mark inside, used as a warning or alert. This emoji is used prominently within social media platform BeReal's core time-sensitive "⚠️ Time to BeReal ⚠️" push notification. This notification is shown when being prompted to share a photo of themselves and their immediate surroundings, with this notification

https://en.wikipedia.org/wiki/Equals_sign
A well-known equality featuring the equal sign. The equals sign (British English) or equal sign (American English), also known as the equality sign, is the mathematical symbol =, which is used to indicate equality in some well-defined sense. In an equation, it is placed between two expressions that have the same value, or for which one studies the conditions under which they have the same value.

https://www.mathematics-monster.com/symbols/Therefore.html
The ∴ Symbol: "Therefore". The ∴ symbol, often pronounced as "therefore", is widely used in both mathematics and logic. This symbol serves as a shorthand notation indicating a conclusion or a resultant deduction from previously stated facts or premises. This lesson covers its meaning and use, with a couple of illustrative examples.

https://math.stackexchange.com/questions/790019/what-is-the-symbol-%E2%89%99-most-commonly-used-for-in-a-mathematical-or-math-related-co
What is the symbol ≙ most commonly used for in a mathematical or math-related context?. LaTeX produces the symbol with \hateq.; The symbol has Unicode codepoint U+2259.; The respective Unicode code chart shows it with the name ESTIMATES and the annotation = corresponds to.Note that the names and annotations there are often not helpful, incomplete, or even misleading.

https://www.mathematics-monster.com/symbols/Minus-Sign.html
Example 1: Subtraction of Numbers: When considering the subtraction of two numbers, the − sign is used to indicate the operation. For instance: 7 − 5 = 2 7 − 5 = 2. In this equation, 5 is subtracted from 7 to yield a result of 2. Example 2: Indicating Negative Values: The − sign is also employed to represent negative quantities.

https://emojipedia.org/check-mark
A thick check mark / tick displayed on some platforms in a handwritten style. Generally displayed in black. Commonly used in lists to signify completed tasks or verification of a statement of fact. Previously shown in red on Samsung and green on Google and Microsoft . Note: this emoji is not supported in Twitter / X names, to minimize confusion

https://www.mathsisfun.com/algebra/brackets.html
Brackets are symbols used in pairs to group things together. When we see things inside brackets we do them first (as explained in Order of Operations ). The parentheses group 3 and 2 together, and 6 and 4 together, so they get done first: Without the parentheses the multiplication is done first: With more complicated grouping we can use

https://wumbo.net/symbols/minus/
The minus symbol is used in math to represent subtraction. Typically, the symbol is used in an expression like this: In plain language, this expression represents 6 minus 5. Note, the code point of this character is different from the hyphen symbol (-) on the keyboard even though they are usually used to mean the same thing. The minus symbol is

https://math.stackexchange.com/questions/2864497/what-does-%E2%A9%94-mean
In the language "R" the operators "|" and "&" indicate the logical operations OR and AND, but the longer form evaluates left to right examining only the first element of each vector. Source: "Logical operators in R". In the language JavaScript bitwise operators ("|" and "&") treat their operands as a sequence of 32 bits (zeroes

https://en.wikipedia.org/wiki/%E2%88%82
The character ∂ ( Unicode: U+2202) is a stylized cursive d mainly used as a mathematical symbol, usually to denote a partial derivative such as (read as "the partial derivative of z with respect to x "). [1] [2] It is also used for boundary of a set, the boundary operator in a chain complex, and the conjugate of the Dolbeault operator on

https://wumbo.net/symbols/perpendicular/
In geometry, the perpendicular symbol is used to show that two lines are perpendicular to each other. Visually, the symbol is made up of two lines that form a perpendicular angle.

https://www.mathematics-monster.com/symbols/Tilde-Operator.html
Here, the tilde indicates that 3.14 is an approximation of π. To wrap up, the ∼ symbol is versatile and widely adopted in various mathematical contexts. Its usage mainly revolves around the concepts of similarity, equivalence, or approximation. It's an efficient way to convey these concepts without the need for verbose explanations.

https://math.stackexchange.com/questions/4380266/meaning-of-the-symbol-%E2%89%A1
It can mean "is defined to be equal to" (for which another common symbol is := := ). Another meaning is "is identically equal to" (for example we write sin2 x +cos2 x ≡ 1 sin 2. ⁡. x + cos 2. ⁡. x ≡ 1 to emphasize that this equation holds for all x ∈R x ∈ R (actually for all x ∈C x ∈ C as well)). It can also mean congurence as