Import["file", "TerminatedString"] imports a file as a list of null-terminated character strings.
Export["file", str, "TerminatedString"] exports a string as a null-terminated sequence of 8-bit characters.
Export["file", {str1, str2, ...}, "TerminatedString"] exports a list of strings to sequences of 8-bit character codes, each terminated by a null character.
Import["file", "TerminatedString"] returns a list of strings.
Export["file", expr, "TerminatedString"] creates a text file from the OutputForm representation of expr.