The intrinsic value of each worthy character that appears inside a
string denotation is itself. The string "/abc", for example,
contains a slash character followed by the three letters a,
b and c. A string break is a sequence of worthy
characters that can occur inside a string or character denotation,
that denotes some particular character.
String break sequences start with a break character. The Algol
68 Standard Hardware Representation allows implementations to define
their own set of string breaks, but insists that the apostrophe should
be the escape character. An example would be '/ to denote a
newline character, for example. The GNU Algol 68 compiler deviates
from this and uses the backslash character to start string breaks
emulating the familiar escape sequences used in C-like languages.