How to remove duplicate values from a JavaScript array?

We can use array.indexOf method to check a value exists or not. See below example to remove duplicate values.

let duplicates = ['delhi','kanpur','kanpur','goa','delhi','new york'];

function removeDuplicatesValues(arr){
    let unique_array = [];
    for(let i = 0;i < arr.length; i++){
        if(unique_array.indexOf(arr[i]) == -1){
            unique_array.push(arr[i])
        }
    }
    return unique_array
}

console.log(removeDuplicatesValues(duplicates));