Wikipedia:Manual of Style/Character Table 2

Potentially confusing or technically problematic characters |
Category	coded form (direct form)	Notes
Miscellany	&amp; (&) &lt; (<) &gt; (>) &#91; ([) &#93; (]) &apos; (') &#124; (|)	Use these characters directly in general, unless they interfere with HTML or wiki markup. The apostrophe and pipe symbol can alternatively be coded with {{'}} and {{!}}. See also character-substitution templates.
Greek letters	&Alpha; (Α) &Beta; (Β) &Epsilon; (Ε) &Zeta; (Ζ) &Eta; (Η) &Iota; (Ι) &Kappa; (Κ) &Mu; (Μ) &Nu; (Ν) &Omicron; (Ο) &Rho; (Ρ) &Tau; (Τ) &Upsilon; (Υ) &Chi; (Χ) &kappa; (κ) &omicron; (ο) &rho; (ρ)	In isolation, use coded forms to avoid confusion with similar-looking Latin letters; in a Greek word or text, use the direct characters.
Quotes	&lsquo; (‘) &rsquo; (’) &sbquo; (‚) &ldquo; (“) &rdquo; (”) &bdquo; („) &acute; (´) &prime; (′) &Prime; (″) &#96; (`)	Can be confused with straight quotes (" and ') and one another.
Dashes, minus, hyphens	&ndash; (–) &mdash; (—) &minus; (−) - (hyphen) &shy; (soft hyphen)	Easily confused with one another depending on font. For endash, emdash, and minus, both direct and coded forms are used. Soft hyphens should always be coded, never direct. Plain hyphens are usually direct, though at times (e.g. Help:CS1#Pages), {{hyphen}} may be preferable to avoid confusion. See MOS:DASH, MOS:SHY, and MOS:MINUS.
Whitespace and non-printing	&nbsp; &thinsp; &hairsp; &lrm; &rlm; &zwnj;	In direct form these are essentially impossible to identify reliably. See MOS:NBSP (non-breaking spaces) and MOS:RTL (text direction).
Math-related	&times; (×) &and; (∧) &or; (∨) &lang; (⟨) &rang; (⟩)	Can be confused with x ^ v < >. In some cases TeX markup is preferred to Unicode characters; see MOS:FORMULA. × is used in article titles, and for hybrid species.
Non-English punctuation	&lsaquo; (‹) &rsaquo; (›)	Can be confused with <>. Generally only used for non-English languages and math notation.
Dots	&sdot; (⋅) &middot; (·) &bull; (•)	Can be confused with one another. Interpunct (&middot;) is common in horizontal lists and to indicate syllables in words. The multiplication dot (&sdot;) is used for math.