Literacy is the ability to read or write a given script (alphabet, syllabary, logographic characters, etc.). It is possible to be literate but be unable to speak and/or understand a language, or be illiterate but speak/understand a language.
Logograph
Definition
In a written language, a logogram or logograph is a written character that represents a word or morpheme. Chinese characters are logograms, as are many hieroglyphic and cuneiform characters.