let & '(())'

---

while

#!/bin/bash
n=1
while [ $n -le 5 ]
do
	echo "Welcome $n times."
    let n=n+1
done

#!/bin/bash
n=1
while (( N <= 5))
do
	echo "Welcome $n times."
    n=$(( n+1 ))
done

Infinite Loop

---

until

---

Break & Continue

---

select

file Select

---

for

---

function

Local Variable

Return

check file