Parameter & Argument
A parameter is the named slot in a function's definition; an argument is the actual value you pass in.
When you define def greet(name):, name is a parameter — an empty labeled slot. When you call greet("Nour"), the value "Nour" is an argument — what actually fills the slot this time.
Programmers mix the two words daily and everyone survives, but the distinction is real: parameters live in the definition, arguments live in the call. Slots versus fillings.
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