What is a PHP function?
Why Interviewers Ask This
Foundational questions like this help interviewers calibrate the rest of the interview. A confident, accurate answer signals that you have solid PHP basics — a prerequisite for any developer role.
Answer
A function in PHP is a reusable block of code that performs a specific task. Define with the function keyword: function greet(string $name): string { return "Hello, $name!"; }. PHP functions support default parameter values, type declarations (PHP 7+), and return type declarations. PHP passes arguments by value by default — to pass by reference, prefix the parameter with &: function increment(int &$n): void { $n++; }. PHP also has variable functions (storing a function name in a variable and calling it), anonymous functions (closures), and arrow functions (PHP 7.4+). Functions are globally scoped by default in PHP.
Common Mistake
Rushing to answer is a common mistake. Take two seconds to structure your response: definition → example → trade-off. This structure makes complex PHP answers easy to follow.
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