Подробно про метод filter() в JavaScript.

https://medium.com/@stasonmars/%D0%BF%D0%BE%D0%B4%D1%80%D0%BE%D0%B1%D0%BD%D0%BE-%D0%BF%D1%80%D0%BE-%D0%BC%D0%B5%D1%82%D0%BE%D0%B4-filter-%D0%B2-javascript-1fcb239a0d74