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://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"). It is also used for boundary of a set, the boundary operator in a chain complex, and the conjugate of the Dolbeault operator on smooth differential forms over a complex manifold.

https://www.khanacademy.org/math/cc-1st-grade-math/cc-1st-add-subtract/cc-1st-equal-sign/v/equal-sign
Six plus one, the answer is seven. Eight minus two, the answer is six. That's not quite right. What the equal sign is saying is that what's on the left side is the same amount, the same quantity, as what is on the right-hand side. It's saying that two plus three is the same thing as five. And you didn't have to write it this way.

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

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://math.stackexchange.com/questions/846707/what-does-%E2%88%88-mean
$\begingroup$ An added note, since the wiki article does not mention it: one can look at ∈ meaning 'is' through the prism of sets representing the common property held by all its elements. e.g. Even = {0,2,4,..} and 'a ∈ Even' can be read as 'a is Even' $\endgroup$

https://www.mathsisfun.com/algebra/symbols.html
Symbols in Algebra Common Symbols Used in Algebra. Symbols save time and space when writing. Here are the most common algebraic symbols:

https://en.wiktionary.org/wiki/%E2%89%88
Eric Weisstein, Wolfram Mathworld, "Approximately Equal": If two quantities A and B are approximately equal, this is written A ≈ B. Synonyms: ~=, ≅. ( topology) Homeomorphic to.

https://math.stackexchange.com/questions/3958074/what-is-the-meaning-of-%E2%8A%8A
3 Answers. Short answer: A ⊊ B A ⊊ B means that A A is a subset of B B and A A is not equal to B B. Long answer: There is some confusion on mathematical textbooks when it comes to the symbols indicating one set is a subset of another. It's relatively clear what the symbol " ⊆ ⊆ " means. This symbol is more or less universally understood

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://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://emojipedia.org/smiling-face
A classic smiley. A yellow face with a modest smile, rosy cheeks, and soft, closed eyes. Many platforms, including Apple, feature relaxed eyebrows. Conveys a wide range of warm, positive feelings, including love, happiness, and gratitude. Similar to 😊 Smiling Face With Smiling Eyes, which has a broader smile, no eyebrows, and smiling eyes.

https://en.wikipedia.org/wiki/Division_sign
The division sign (÷) is a mathematical symbol consisting of a short horizontal line with a dot above and another dot below, used in Anglophone countries to indicate the operation of division.This usage, though widespread in some countries, is not universal and the symbol has a different meaning in other countries. Its use to denote division is not recommended in the ISO 80000-2 standard for

https://www.thepunctuationguide.com/slash.html
The one inarguably acceptable use of the slash in formal writing pertains to poetry. The slash, with one space on either side, indicates a line break. In choosing your path in life, you might consider the words of Robert Frost, in his poem "The Road Not Taken": "I took the one less traveled by, / And that has made all the difference.".

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/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