Explain what recursive functions mean in programming and how they work.

A recursive function is a function that calls itself to solve a problem. In programming, recursion is used to break down a complex problem into simpler subproblems of the same type.

Working principle:

• The function calls itself with a modified argument, bringing the solution closer to the base case.
• The base case is a condition where recursion stops to avoid infinite calls.

Example in Go — calculating the factorial of a number:

package main
import "fmt"

func factorial(n int) int {
    if n == 0 {
        return 1 // base case
    }
    return n * factorial(n-1) // recursive call
}

func main() {
    fmt.Println(factorial(5)) // 120
}

Recursion is convenient for working with trees, graphs, and dividing tasks, but requires caution to avoid stack overflow.