See section String Type , and section Vector Type . This is called zero-origin indexing. In principle, if you wish to have an array of characters, you could use either a string or a vector. They occupy one-fourth the space of a vector of the same elements. Strings are printed in a way that shows the contents more clearly as characters.
Strings can hold text properties.
See section Text Properties . For example, you cannot insert a vector of characters into a buffer the way you can insert a string. See section Strings and Characters . In this section, we describe the functions that accept both strings and vectors. This function returns the index th element of array .