Choosing a path with conditions
Conditional statements let a program respond differently to different data. Python checks the if branch first, then each elif branch in order, and finally else when no earlier condition is true.
Order conditions from specific to general
Overlapping conditions can produce surprising results if a broad condition appears before a more specific one. Think about boundary values such as zero, maximum limits and empty values before writing the branches.
Truthy and falsy values
Empty strings, empty collections, zero and None are false in a boolean context. This can make code concise, but use explicit comparisons when the difference between an empty value and a missing value matters.
Practice: write a grading system with clear score ranges and test values exactly at every boundary.
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