(Latin: letter; a graphic symbol, a written character, an alphabetic sign)

transliteration (s) (noun), transliterations (pl)
The act or results of representing letters or words in the characters of another alphabet, language, or script: Sam was unable to talk clearly; so, he was communicating with others by producing his conversations in a sign language and they were doing the same for him.
transliterator (s) (noun), transliterators (pl)
Someone who can translate or write words or letters in the characters or alphabet of another language.