Booleans

The Boolean data type has two, and only two, possible values, namely, True and False. In Python, you can produce a Boolean value by writing either True or False, starting with a capital T or F respectively:

>> True
>> False

Boolean values can be combined using bitwise operators:

• The and operator yields True if the value on the left and the value on the right are both True
• The or operator yields True if at least one of the items on the left or right is True

The following are some examples using bitwise operators:

>> True and True
>> True and False
>> True or False
>> False or False

Logical operators can be used to produce Boolean values from other data types by comparing values:

• The == operator yields True if the values on either side are equal
• The > operator yields True if value to the left is greater than the value to the right
• The < operator yields True if the value to the right is greater than the value to the left

The following are some examples using logical operators:

>> 1 == 2
>> 1 == 1
>> 1 < 2
>> 1 < 0
>> 1 > 2
>> 2 > 1
>> "abc" == "abc"
>> "abc" == "cba"

Boolean values are good to make decisions within computer programs. You will see this when I introduce if statements later in the chapter. They are also good to store simple yes/no data entries, such as whether a particular individual lives in New York or whether a transaction has been completed.