let arr = [6,5,3,1]

for (let outerLoopPosition = 1; outerLoopPosition < arr.length; outerLoopPosition++) {

let outerLoopVal = arr[outerLoopPosition];

let comparePosition = outerLoopPosition - 1;

let compareVal = arr[comparePosition]

// 1 current arr [ 6, 5, 3, 1 ]

// 1 outerLoopPosition 1 outerLoopVal 5

// 1 comparePosition 0 compareVal 6

// 2 current arr [ 5, 6, 3, 1 ]

// 2 outerLoopPosition 2 outerLoopVal 3

// 2 comparePosition 1 compareVal 6

// 3 current arr [ 3, 5, 6, 1 ]

// 3 outerLoopPosition 3 outerLoopVal 1

// 3 comparePosition 2 compareVal 6

while (comparePosition > -1 && outerLoopVal < compareVal) {

// 1 comparePosition 0 is greater than -1 and outerLoopVal 5 is less than 6

// 1 move comparePosition 0 with compareVal 6 to position 1

// 1 new arr [ 6, 6, 3, 1 ]

// 2 comparePosition 1 is greater than -1 and outerLoopVal 3 is less than 6

// 2 move comparePosition 1 with compareVal 6 to position 2

// 2 new arr [ 5, 6, 6, 1 ]

// 2 comparePosition 0 is greater than -1 and outerLoopVal 3 is less than 5

// 2 move comparePosition 0 with compareVal 5 to position 1

// 2 new arr [ 5, 5, 6, 1 ]

// 3 comparePosition 2 is greater than -1 and outerLoopVal 1 is less than 6

// 3 move comparePosition 2 with compareVal 6 to position 3

// 3 new arr [ 3, 5, 6, 6 ]

// 3 comparePosition 1 is greater than -1 and outerLoopVal 1 is less than 5

// 3 move comparePosition 1 with compareVal 5 to position 2

// 3 new arr [ 3, 5, 5, 6 ]

// 3 comparePosition 0 is greater than -1 and outerLoopVal 1 is less than 3

// 3 move comparePosition 0 with compareVal 3 to position 1

// 3 new arr [ 3, 3, 5, 6 ]

arr[comparePosition + 1] = arr[comparePosition];

comparePosition--;

compareVal = arr[comparePosition]

}

// 1 outer loop pre-final arr [ 6, 6, 3, 1 ]

// 2 outer loop pre-final arr [ 5, 5, 6, 1 ]

// 3 outer loop pre-final arr [ 3, 3, 5, 6 ]

arr[comparePosition + 1] = outerLoopVal

// 1 set outerLoopVal 5 to (comparePosition + 1) position: 0

// 1 outer loop final arr [ 5, 6, 3, 1 ]

// 2 set outerLoopVal 3 to (comparePosition + 1) position: 0

// 2 outer loop final arr [ 3, 5, 6, 1 ]

// 3 set outerLoopVal 1 to (comparePosition + 1) position: 0

// 3 outer loop final arr [ 1, 3, 5, 6 ]

}

// final [ 1, 3, 5, 6 ]