Stop words aren’t indexed and therefore are ignored when they’re entered in a query. These are words that don't influence the result of a search query, such as articles and prepositions (a, an, the, in, on, for). This has a significant effect on the size of the index and the efficiency of the search result.
Common Stop Words: a, an, and, are, as, at, be, but, by, for, if, in, into, is, it, no, not, of, on, or, s, such, t, that, the, their, then, there, these, they, this, to, was, will, with, x
While common stop words don't greatly impact the meaning of a
search, there might be exceptions to this for some merchandisers. For example, if you were
doing a search on movie titles, The Natural is a different movie than
A Natural. Consider carefully what words you can safely prevent from
being indexed.
You can import and export stop words as part of an index definition file.