Conditionals

Conditionals are statements that do different things under different conditions. For example, you might want your program to do one thing for even numbers, and a different thing for odd numbers. We use if, elif (short for “else if”), and else to outline the conditions and the code that should run for
each condition.
For each if and elif line, we write a condition using comparison:

• equal to: ==
• not equal to: !=
• less than, less than or equal to: <, <=
• greater than, greater than or equal to: >, >=
• is/is not, is in/is not in

The else catches anything that doesn’t get caught by the if/elif statements.

Pay attention to the colons : and the indentation in the conditional at left. These are both important! You’ll get a syntax error if you leave them out. Syntax means the rules about structure and formatting, and a syntax error means you’ve broken one of those rules!

An if is the only necessary part of a conditional: you can have as many elifs as you want, or none at all, and you can put an else at the end or not.