gistfile1.txt

[8] pry(main)> show-doc String

From: string.c @ line N/A:

A <code>String</code> object holds and manipulates an arbitrary sequence of
bytes, typically representing characters. String objects may be created
using <code>String::new</code> or as literals.

Because of aliasing issues, users of strings should be aware of the methods
that modify the contents of a <code>String</code> object.  Typically,
methods with names ending in ``!'' modify their receiver, while those
without a ``!'' return a new <code>String</code>.  However, there are
exceptions, such as <code>String#[]=</code>.
[9] pry(main)>