Sup: ¹ ² ³ ⁴ ⁵ ⁶ ⁷ ⁸ ⁹ ⁰ ⁽ ⁾ ⁿ
Sub: ₁ ₂ ₃ ₄ ₅ ₆ ₇ ₈ ₉ ₀ ₍ ₎
← → ↑ ↓ ↖ ↘ ↔ ↕ ⤡ ⤢
￩ ￫ ￪ ￬ ⇤ ⇥
⇐ ⇒ ⇑ ⇓ ⇔ ⇕ ⇄ ⇆ ⇅ ⇵
↰ ↱ ↲ ↳ ↴ ↵
↺ ↻ ↶ ↷ ⥀ ⥁
‣ ◄ ► ▲ ▼ ⏴ ⏵ ⏶ ⏷ ◂ ▸ ▴ ▾ ◃ ▹ ▵ ▿
❮ ❯ ❰ ❱
… ≤ ≥ ≠ ~ ≈ ± ∞ ÷ × ø Ø ∑ ∪ ƒ ¬ √ ∛
’ ’ “ ” ‹ › « » ⋘ ⋙ ∧ ∨
≡ ≋ ⫻ ⫼ ⋮ ⋯ ⋰ ⋱ 𐬽 𐬼 ⸫ ⸪ ∷ ⌗
⊕ ⊖ ⊗ ⊘ ⊙ ⊛ ⍟ ⊞ ⊟ ☑ ⊠ ⊡
• · ■ ◼ ◻ ▪ ▫ █
♥ ☀︎ ☼ ☽ ☾ ★ ☆
♠︎ ♣︎ ♥︎ ♦︎ ♤ ♧ ♡ ♢
⌨ ⌘ ⌥ ⌃ ⇧ ⇪ ⌫ ⌦ ↩ ⏎ ⌤ ␛ ⎋ ⇞ ⇟ ↖ ↘ ⌧ ␢ ␣
⏵ ⏸ ⏯ ⏹ ⏺ ⏮ ⏭ ⏻ ⏼ ⏾ ⏏ ⚙︎
👍 👎 👌 🤙 🤘 👊 👋 ☝️ 👈 👉 👆 👇
😀 😁 😉 😜 🤔 🤭 🤫 🙄 😎 🤓 🥳 🤩 🤯 😱 😡
❤️ ⭐️ ⚠️ 🚧 ⏳ 💡 💾 📕 📌 🧨 🪄
✅ ❌
🚀 🍺 🍻 🍾 ⚡️
🍒 🧞♂️ 🤖 ☠️ 🛠 ⚙️
┌─┬─┐ ┏━┳━┓ ╔═╦═╗ ╭─┬─╮
├─┼─┤ ┣━╋━┫ ╠═╬═╣ ├─┼─┤
│ │ │ ┃ ┃ ┃ ║ ║ ║ │ │ │
└─┴─┘ ┗━┻━┛ ╚═╩═╝ ╰─┴─╯
Wikipedia
Unicode: U+00A0
UTF-8: 0xC2 0xA0
HTML: ,  
macOS: Copy non-breaking space to clipboard:
printf "\xC2\xA0" | pbcopy
Wikipedia
Abbreviated: ZWSP
Unicode: U+200B
HTML: ​, ​ or ​
macOS: Copy zero-width space to clipboard:
printf "\u200B" | pbcopy
HTML Entity GLYPH NAME
 Apple
⌘ ⌘ Command, Cmd, Clover, (formerly) Apple
⌃ ⌃ Control, Ctl, Ctrl
⌥ ⌥ Option, Opt, (Windows) Alt
⇧ ⇧ Shift
⇪ ⇪ Caps lock
⏏ ⏏ Eject
↩ ↩ Return, Carriage Return
↵ ↵ ↵ Return, Carriage Return
⏎ ⏎ Return, Carriage Return
⌤ ⌤ Enter
⌫ ⌫ Delete, Backspace
⌦ ⌦ Forward Delete
⎋ ⎋ Escape, Esc
→ → → Right arrow
← ← ← Left arrow
↑ ↑ ↑ Up arrow
↓ ↓ ↓ Down arrow
⇞ ⇞ Page Up, PgUp
⇟ ⇟ Page Down, PgDn
↖ ↖ Home
↘ ↘ End
⌧ ⌧ Clear
⇥ ⇥ Tab, Tab Right, Horizontal Tab
⇤ ⇤ Shift Tab, Tab Left, Back-tab
␢ ␢ Space, Blank
␣ ␣ Space, Blank