Cheat sheet:

• symbols: μ Ω τ ω π σ δ η ∞ Δ ε λ ° ∠ ± ÷ ≈ ≠ × ‰ √ ½ ¼ ¾ ² ³
• non-breaking space:  
• narrow, non-breaking space:  
• subscript: <sub></sub>
• superscript: <sup></sup>

Assign new tags:

• pico [raspberry-pi]
• [qspi]
• [electron-hole]