What is "?:" operator [duplicate]

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Can someone explain me why do we use ?: operator . Im doing my homework and I need to rewrite this code in if/else clause .But I dont know the operator .

teenager = (age >= 13 && age < 20) ? 1 : 0 ;ıl

This would be my code; if(age >= 13 && age < 20) blablabla else printf("0")