See also Unicode/List of useful symbols on Wikibooks.
spacing: ` ´ ^ ˜ ¯ ˘ ˙ ¨ ˚ ˝ ˇ ¸ ˛
combining: ◌̀ ◌́ ◌̂ ◌̃ ◌̄ ◌̆ ◌̇ ◌̈ ◌̊ ◌̋ ◌̌ ◌̧ ◌̨
lexical ligatures: Æ æ Œ œ ẞ ß
etc.: Ð ð Ə ə İ ı Ŋ ŋ Ø ø ſ Þ þ
joiners: cgj͏cgj (ij → i͏j) zwnjzwnj (fi → fi)
digraphs (deprecated): DZ Dz dz DŽ Dž dž IJ ij LJ Lj lj NJ Nj nj
typographic ligatures (deprecated): ff ffi ffl fi fl
per‐X: % ‰ ‱
ordinals: ª º
end‐of‐sentence: … ! ¡ ? ¿ ‽ ⸘
dashes:
currency: $ ¢ £ ¥ € ¤
quotes: ‘ ’ ‚ ‛ “ ” „ ‟ ‹ › « »
bullets: • ‣ ⁃ ☙
markup: " ‸ § ¶
pronunciation: ʹ ʺ ‧
marks: * † ‡
spaces:
et: & 🙰 🙲 🙵
etc.: ·
arithmetic: + − × ⋅ ÷ ∕ √ ∛ ∜ ( )
geometry: ⌀ ∟ ∠ ∡ ∢ ∥ ∦
unary: | ⌈ ⌉ ⌊ ⌋ ± ∓ ℜ ℑ
adornments: ′ ″ ‴ ⁗
(in)equality: = ≠ ≡ ≜ ≝ ≟ < > ≤ ≥ ≪ ≫ ∼ ≃ ≅ ≈ ∝
ratios: ∶ ∷ ◌⁄◌ ⅟◌ ½ ⅓ ⅔ ¼ ¾ ⅕ ⅖ ⅗ ⅘ ⅙ ⅚ ⅐ ⅛ ⅜ ⅝ ⅞ ⅑ ⅒
logic: ∀ ∃ ∄ ¬ ∧ ∨ → ↔ ℩
proofs: ⇒ ⇔ ⊤ ⊥ ∴ ⊢ ⊨ ∎
sets: { } ∁ ∅ ∆ ∈ ∉ ∊ ∖ ∩ ∪ ⊂ ⊄ ⊆ ⊈ ⊖ 𝒫
calculus: ◌̇ ◌̈ ◌⃛ ◌⃜ ∆ ⅆ ∂ ∫ ∬ ∭ ∮ ∯ ∰ ℱ ℒ
n‐ary: ∑ ∏ ⋀ ⋁ ⋂ ⋃
units: ° µ Ω Å K °C °F ′ ″ ⏍
Greek: α β Γ γ Δ δ ε ζ η Θ θ ι κ Λ λ μ ν Ξ ξ Π π ρ Σ σ τ υ Φ φ χ Ψ ψ Ω ω
non‐Greek: ℰ ℯ ℏ ℩ ℓ ϵ ϴ ϰ ϱ ς ϕ ϖ
domains: ℙ ℕ ℤ ℚ ℝ ℂ ℍ
infinities: ∞ 𝔠 ℵ ℶ ℷ ℸ
relations: ∣ ∤ ≺ ≻ ≼ ≽
vectors: ◌⃑ ‖ ⟨ ⟩ ∇
matrices: ⋮ ⋯ ⋰ ⋱ [ ] ⧵
super/subscript: ⁰ ¹ ² ³ ⁻ ₀ ₁ ₂ ₃ ₋
spaces: = 5 /
etc.: ∗ ∘ ⊕ ⊗
legal: © ® ℗ ℠ ™ ℮
keys: ⌘ ⌥ ⌦ ⌫ ⏎ ⇞ ⇟ ⇤ ⇥ ⇧ ⇪
computer: ␀ ␈ ␉ ␊  ␍ ␛ ␡ ␢ ␣
abbreviations: ℅ № ℞ ℹ⃝
pointers: ☚ ☛ ☜ ☝ ☞ ☟
arrows: ← ↑ → ↓ ↔
smileys: ☺ ☻ ☹
music: ♩ ♪ ♫ ♬ ♭ ♮ ♯
checkmarks: ✓ ✗ ☐ ☑ ☒
gender: ♀ ♂ ⚢ ⚣ ⚤ ⚥ ⚦ ⚧ ⚪︎ ⚲
suits: ♠ ♡ ♢ ♣ ♤ ♥ ♦ ♧
etc.: ⏚ ☮ ♻ ⚠
common Latin‐1: À
common non‐Latin‐1 2‐byte UTF‐8: Ж
common 3‐byte UTF‐8: ☀
common non‐BMP (4‐byte UTF‐8): 😂
object replacement character: 
replacement character: �
not a character:
private use: