⊥ ∥ ∠ ⌒ ⊙ ≡ ≌ △
2. Algebraic symbols
∝ ∧ ∨ ~ ∫ ≠ ≤ ≥ ≈ ∞ ∶
3. Operation symbols
Such as plus sign (+), minus sign (-), multiplication sign (× or), division sign (÷ or/), union of two sets (∩), intersection (∩), root sign (√), logarithm (log, lg, ln) and ratio (:).
4. Symbol set
∪ ∩ ∈
5. Special symbols
∑π(π)
6. Inference symbols
| a |⊥∽△∞∩∩≦≦≤∈ⅲ
↑ → ↓ ↖ ↗ ↘ ↙ ∥ ∧ ∨
& amp;
① ② ③ ④ ⑤ ⑥ ⑦ ⑧ ⑨ ⑩
Γ Δ Θ Λ Ξ Ο Π Σ Φ Χ Ψ Ω
α β γ δ ε ζ η θ ι κ λ μ ν
ξ ο π ρ σ τ υ φ χ ψ ω
Ⅰ Ⅱ Ⅲ Ⅳ Ⅴ Ⅵ Ⅶ Ⅷ Ⅸ Ⅹ Ⅺ Ⅻ
ⅰ ⅱ ⅲ ⅳ ⅴ ⅵ ⅶ ⅷ ⅸ ⅹ
∈ ∏ ∑ ∕ √ ∝ ∞ ∟ ∠ ∣ ∥ ∧ ∨ ∩ ∪ ∫ ∮
∴ ∵ ∶ ∷ ∽ ≈ ≌ ≒ ≠ ≡ ≤ ≥ ≦ ≧ ≮ ≯ ⊕ ⊙ ⊥
⊿ ⌒ ℃
Index 0 123: O 123
7. Symbol of quantity
Such as: I, 2+i, A, X, natural logarithm base E, pi.
8. Relationship symbols
For example, = is equal sign, ≈ is approximate sign, ≠ is unequal sign, > is greater than sign,