map() , filter() , reduce() etc.
The following page gives a good overview over the various methods you can use on the array prototype.
Feel free to click through them and refresh your knowledge as required:
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array
Particularly important are:
map() => https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/map
find() => https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/find
findIndex() => https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/findIndex
filter() => https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/filter
reduce() => https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/Reduce?v=b
concat() => https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/concat?v=b
slice() => https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/slice
splice() => https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/splice