I just rewrite above code. In for loop i will be increase from 0 to 5, when i reaches to 6, it will be return through i<=5. and push 6 to arr. that's it.

const arr = []
for(var i=0 ; i<=5 ; i++){} // i will be from 0 to 6.
{ 
  arr.push(i)
}
console.log(arr) // [6]

The semicolon between round bracket and curly stops the statement.

You can do the following:

• If you are trying to push the numbers 0 to 5 into the array, then remove the semicolon (;), else it will cause reference error since i is a let variable.
• If you want to push only the last value of i (which is 6) then please use var instead of let inside for loop.