Facets and filters are both ways to narrow down a search. These two can be similar in some aspects since both help people find what they are looking for in a particular way. Facets are a way of grouping data into logical groups. One can apply multiple facets and find the relevant ones.
Instead, filters can be broader, and multiple options might not be applied. One can choose a filter before the search query, and it won’t be changed. Facets offer more options, and filters provide main categories of specific information.