Simple data types
- Atoms
Atoms are essentially user-defined names, but have no meaning on their own.
They can optionally be enclosed in single quotes, e.g.
foo, 'blah', x etc.
- Numeric values
Prolog supports traditional integer and floating point numeric values,
e.g. 32, 123.456, etc.
- Character values
Characters can be represented by preceding them with 0',
e.g. 0'z for the lowercase z character.
- String values
Strings in prolog are represented within double quotes, e.g. "This is a string",
which internally are stored as lists of the characters' ascii values.