A literal is a constant value for some of the built-in types. Here are some examples of literals.

>>> a = 1 # 1 is an integer literal >>> b = 2.3 # 2.3 is a floating point literal >>> c = False # False is a boolean literal >>> d = 5L # 5L is a long integer literal >>> e = 8 + 6j # 8 + 6j is a complex literal >>> f = "Hello" # "Hello" is a string literal

An expression is composed of variables and operators. The simplest expression is just a variable. The value of an expression is evaluated before it is used.

These are the arithmetic operators that operate on numbers (integers or floats). The result of applying an arithmetic operator is a number.

- Addition: +
- Subtraction: -
- Multiplication: *
- Division: /
- Remainder: %
- Exponentiation: **

There are 6 comparison operators. The result of applying the comparison
operators is a Boolean - *True* or *False*.

- Equal to: ==
- Not equal to: !=
- Greater than: >
- Greater than or equal to: >=
- Less than: <
- Less than or equal to: <=

You may apply the comparison operator between two operands like so (a > b). You can also apply the comparison operators in sequence like so (a > b > c). However, this is a practice that is not recommended.

In Python, we have two Boolean literals - *True* and *False*.
But Python will also regard as *False* - the number zero (0), an
empty string (""), or the reserved word *None*. All other values
are interpreted as *True*. There are 3 Boolean operators:

*not*: unary operator that returns*True*if the operand is*False*and vice versa.- x
*and*y: if x is false, then that value is returned; otherwise y is evaluated and the resulting value is returned. - x
*or*y: if x is true, then that value is returned; otherwise y is evaluated and the resulting value is returned.

a | not a |

F | T |

T | F |

a | b | a and b |

F | F | F |

F | T | F |

T | F | F |

T | T | T |

a | b | a or b |

F | F | F |

F | T | T |

T | F | T |

T | T | T |

The bitwise operators include the AND operator ** &**, the OR
operator ** |**, the EXCLUSIVE OR operator ** ^** and the unary
NOT operator **~**. The bitwise operators applies only to integer
types.

a | b | a ^ b |

0 | 0 | 0 |

0 | 1 | 1 |

1 | 0 | 1 |

1 | 1 | 0 |

Shift operators are applied only to integer types.

- x << k : shift the bits in x, k places to the left. Multiplication by (2 ** k).
- x >> k : shift the bits in x, k places to the right filling in with the highest bit on the left hand side. Division by (2 ** k).

Python evaluates an expression from left to right except for assignment. In an assignment, the right-hand side is evaluated before the left-hand side. Refer to the operator precedence to determine the order in which the operations are performed.