In certain situations, we want to find out whether the given document should be included or not; that is, a simple binary answer. On the other hand, there are other types of queries which are relevance-based. Such relevance-based queries also return a score against each document to say how well that document fits the query. Most structured queries do not need relevance-based scoring, and the answer is a simple yes/no for any item to be included or excluded from the result. These structured search queries are also referred to as term level queries.

Let us understand the flow of a term-level query's execution:

As you can see, the figure is divided into two parts. The left half of the figure depicts what happens at the time of indexing, and the right half of the figure depicts what happens at query time...