Booleans

In an upcoming discussion on automatic conversion, we will see how values can be interpreted as different types. When converted to Booleans, almost all values are true, with the following exceptions:

• false
• "false"
• ""
• 0
• -0
• null
• undefined
• NaN

Warning to users of Python: notice that the keywords true and false are not capitalized.

The function Boolean() changes the type of a value to a Boolean.

In this example, notice that since the variable mystery has not been initialized, it has the Boolean value false.