Complex sentence: In C, there are two types of strings: string, which is sometimes called byte string which uses the type char s as code units (one char is at least 8 bits), and wide string which uses the type wchar_t as code units.
Split into simpler sentences: In C, there are two types of strings: string, which is sometimes called byte string, and wide string. A byte string contains the type char s as code units (one char is at least 8 bits), whereas a wide string contains the type wchar_t as code units.