[] are VERY underpowered in JS compared to Python. Here are some major differences/uses:

  • You can use square brackets [ ] to access elements, but only in one direction from start to end.
  • Basically used to get individual characters.
  • For mutable structures, you can change elements like arr[2] = "two"
  • You cannot slice using [ ] methods.
  • You cannot get last element using [-1]