title_body: How to choose a writing system for a conlang?
upvoted_answer: The answer mostly depends on your grammar and phonotactics:
  
  Alphabets
  
  Examples: Latin, Ogham, Mongolian. Alphabets are a pretty reasonable writing system for most spoken languages. I think there's a good reason why the majority of languages with standard written forms use some sort of alphabet. That said, they seem to take a long time to develop, so alphabets are unlikely for concultures that recently discovered writing. 
  
  Abjads
  
  Examples: Arabic, Hebrew, Tifinagh. Abjads are good for languages with few vowels and very few minimal pairs distinguished by vowels. It's especially good in languages with triconsonental roots or other forms that undergo dramatic vowel shift as part of regular grammatical processes to improve coherence across grammatical forms.
  
  Abugidas
  
  Examples: Devanagari, Ge'ez (Ethiopic), Canadian Aboriginal Syllabics. Abugdias are pretty good for languages with relatively simple syllable structure (ideally not more complex than (C)CV(C)). Based on the real world, it seems that they're best suited for languages with a high number of tones or phonations.
  
  Syllabaries
  
  Examples: Hiragana*, Vai, Cherokee. Syllabaries are really only appropriate in languages with relatively simple phonology, ideally not more than (C)V (or adopt a pseudo-syllabary like the kana with separate symbols for coda consonants). Otherwise the number of characters grows exponentially, or will not do a very good job representing all segments of the language, though this is not necessarily a dealbreaker (cf. Cherokee).
  
  * Hiragana is not a true Syllabary because each kana actually represents a mora, not a syllable.
  
  Logographies
  
  Examples: Chinese, Cuneiform, Mayan. Logographs are best suited to isolating and analytic languages. The earliest writing systems seem to be logographies though, so cultures that only recently discovered writing are most likely to have logographies.