See section Character Type . Strings in Lisp are not terminated by a distinguished character code. Since strings are considered arrays, you can operate on them with the general array functions. Strings use an efficient representation for storing the characters in them, and thus take up much less memory than a vector of the same length. Sometimes you will see strings used to hold key sequences.
Strings are useful for holding regular expressions.
Like a buffer, a string can contain extents in it. These extents are created when a function such as buffer-substring is called on a region with duplicable extents in it. When the string is inserted into a buffer, the extents are inserted along with it. See section Duplicable Extents . See section Text , for information about functions that display strings or copy them into buffers.