5 ways to remove duplicate elements from array in JavaScript | Interview Guide

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It’s a common use case in many projects to need to remove duplicates from an array in JavaScript. For interviews, it’s a common coding challenge to practice for everyone.
Here are seven ways to filter out duplicates from an array and return only the unique values.
The filter method creates a new array of elements that pass the conditional we provide. And any element that fails or returns false, it will not be in the filtered array.
And we can also use the filter method to retrieve the duplicate values from the array by simply adjusting our condition

Sets are a new object type with ES6 (ES2015) that allows you to create collections of unique values.
By using forEach, we can iterate over the elements in the array, and we will push into the new array if it doesn’t exist in the array.

Reduce is always a bit more tricky to understand. The reduce method is used to reduce the elements of the array and combine them into a final array based on some reducer function that you pass.
Adding a unique Method to the Array Prototype
In Javascript the array prototype constructor allows you to add new properties and methods to the Array object.

_.uniq method produces a duplicate-free version of the array, and also we can sort this array by passing the second parameter as true.