⊥ ∥ ∠ ⌒ ⊙ ≡ ≌ △

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,