javascript to remove duplicates from an array

1const names = ['John', 'Paul', 'George', 'Ringo', 'John'];
2
3let unique = [...new Set(names)];
4console.log(unique); // 'John', 'Paul', 'George', 'Ringo'

1unique = [...new Set(arr)];   // where arr contains duplicate elements

1let chars = ['A', 'B', 'A', 'C', 'B'];
2let uniqueChars = [...new Set(chars)];
3
4console.log(uniqueChars);
5
6output:
7[ 'A', 'B', 'C' ]

1uniqueArray = a.filter(function(item, pos) {
2    return a.indexOf(item) == pos; 
3})
4

1let a = [10,20,30,10,30];
2let b = a.filter((item,index) => a.indexOf(item) === index);
3console.log(b); 

1uniqueArray = a.filter(function(item, pos) {
2    return a.indexOf(item) == pos;
3})
4