A conditional is a statement that evaluates to either True or False. For example, enter the following into our REPL:
10 > 5That's the number 10, then a greater sign, then a five. As output, you should get back True. Python looks at the statement, evaluates it (simplifies it), determines that ten is greater than five, and lets us know it's true by returning True as a value.
In Python, a boolean is a type that represents either true or false. They're represented with capital letters: True and False.
One of the most common uses of conditional statements is to compare two objects. We already saw one way to compare using >, or the greater than symbol. For example:
10 > 50Since 10 is less than 50, the above will return False. If we instead use the < sign, as below, the result would be True.
10 < 50You can also check for equality between two objects using the == operator. (That's two equals signs.)
5 == 5That's five, a space, a double equals sign, a space, and a five. The result should be True.
Now try the following:
7 == 4That's seven, a space, a double equals sign, a space, and a four. The result should be False.
You can also compare strings in this way:
"hello" == "goodbye""hello" == "hello"Remember that, to create strings, we surround some text with quotes, in this case double quotes. When using our double equals operator (==) to compare "hello" and "goodbye", we get False, whereas comparing "hello" with "hello" returns True.
Why do we use two equals signs to check for equality? Remember that, when we assign variables, we use one equals sign (=). In Python, one equals sign (=) is used for assigning variables and two equals signs (==) is used for checking equality.