ᴴ : Modifier letter H is used in the Uralic Phonetic Alphabet
ₕ : Subscript small h was used in the Uralic Phonetic Alphabet prior to its formal standardization in 1902
ʰ : Modifier letter small h is used in Indo-European studies
ʮ and ʯ : Turned H with fishhook and turned H with fishhook and tail are used in Sino-Tibetanist linguistics
Ƕ ƕ : Latin letter hwair, derived from a ligature of the digraph hv, and used to transliterate the Gothic letter 𐍈 (which represented the sound [hʷ])
Ⱶ ⱶ : Claudian letters
Ꟶ ꟶ : Reversed half h used in Roman inscriptions from the Roman provinces of Gaul

Ancestors, siblings, and descendants in other alphabets
𐤇 : Semitic letter Heth, from which the following symbols derive
Η η : Greek letter Eta, from which the following symbols derive
𐌇 : Old Italic H, the ancestor of modern Latin H
ᚺ, ᚻ : Runic letter haglaz, which is probably a descendant of Old Italic H
Һ һ : Cyrillic letter Shha, which derives from Latin H
И и : Cyrillic letter И, which derives from the Greek letter Eta
𐌷 : Gothic letter haalArmenian letter ho (Հ)

Derived signs, symbols, and abbreviations
h : Planck constant
ℏ : reduced Planck constant

  
    
      
        
          H
        
      
    
    {\displaystyle \mathbb {H} }
   : Blackboard bold capital H used in quaternion notation

Computing codes
1 and all encodings based on ASCII, including the DOS, Windows, ISO-8859, and Macintosh families of encodings.
For example in le homard (the lobster) the article le remains unelided, and may be separated from the noun with a bit of a glottal stop. Most words that begin with an H muet come from Latin (honneur, homme) or from Greek through Latin (hécatombe), whereas most words beginning with an H aspiré come from Germanic (harpe, hareng) or non-Indo-European languages (harem, hamac, haricot); in some cases, an orthographic ⟨h⟩ was added to disambiguate the [v] and semivowel [ɥ] pronunciations before the introduction of the distinction between the letters ⟨v⟩ and ⟨u⟩: huit (from uit, ultimately from Latin octo), huître (from uistre, ultimately from Greek through Latin ostrea). In Italian, ⟨h⟩ has no phonological value. Its most important uses are in the digraphs ch /k/ and gh /ɡ/, as well as to differentiate the spellings of certain short words that are homophones, for example some present tense forms of the verb avere (to have) (such as hanno, they have, vs. anno, year), and in short interjections (oh, ehi). Some languages, including Czech, Slovak, Hungarian, Finnish, and Estonian use ⟨h⟩ as a breathy voiced glottal fricative [ɦ], often as an allophone of otherwise voiceless /h/ in a voiced environment. In Hungarian, the letter has no fewer than five pronunciations, with three additional uses as a productive and non-productive element of digraphs.