Difference between must_not and filter in elasticsearch

Question

Can someone explain to me what the difference between must_not and filter is in elasticsearch?

E.g. here (taken from elasticsearch definitive guide), why isn\'t must_not

Answer 1

The filter is used when the matched documents need to be shown in the result, while must_not is used when the matched documents will not be shown in the results. For further analysis:

filter:

1. It is written in Filter context.
2. It does not affect the score of the result.
3. The matched query results will appear in the result.
4. Exact match based, not partial match.

must_not:

1. It is written again on the same filter context.
2. Which means it will not affect the score of the result.
3. The documents matched with this condition will NOT appear in the result.
4. Exact match based.