>>1824992ND filter (neutral density = tinted without affecting colours).
Means you can take long exposure shots in bright sunshine for waterfalls, rivers, surf, clouds etc to get motion blur effect, see pic - this is about a 1sec exposure in harsh light. Without filter, 1sec would just be a white frame. (See pic)
Polarising filter takes the reflection off water, glass, leaves etc and makes the sky look amazing. I’ll try to find a comparative shot - it’s after dark here.