var score = [100, 300, 500]
console.log(score[0])

    //配列の値を書き換えるには
    score[2] = 400
    //配列を全て表示するには
    console.log(score)
    //配列は文字列も扱うことができる
    var str = ['taguti', 'sugimoto']
    console.log(str)
    //配列の中に配列を書く
    var m = [
        [1,2,3],
        [4,5,6]
    ]
    console.log(m[1][1])

Debugging with inspector protocol because Node.js v8.9.3 was detected.
node --inspect-brk=24044 配列.js
Debugger listening on ws://127.0.0.1:24044/52ad79a6-4f32-453c-a600-e2cd1b2ce596
100
Array(3) [100, 300, 400]
5
Array(2) ["taguti", "sugimoto"]