Each character in a string is stored in a single byte. Therefore, numbers not in the range 0 to 255 are truncated when stored into a string. This means that a string takes up much less memory than a vector of the same length. Sometimes key sequences are represented as strings. See Character Type , for more information about representation of meta and other modifiers for keyboard input characters.
Strings are useful for holding regular expressions.
Like a buffer, a string can contain text properties for the characters in it, as well as the characters themselves. See Text Properties . All the Lisp primitives that copy text from strings to buffers or other strings also copy the properties of the characters being copied. See Text , for information about functions that display strings or copy them into buffers. See Character Type , and String Type , for information about the syntax of characters and strings.