ELI5: Explain Like I'm 5

Cuckoo filter

A cuckoo is a bird that lays its eggs in other birds' nests. Cuckoo filter works in a similar way, but instead of birds and eggs, we have a list of items that need to be checked if they are present or not.

Imagine we have a list of different fruits, such as apples, bananas, and oranges. We need to remember if a certain fruit is in the list or not. Instead of a normal list, we're going to use two different bird's nests, and we're going to call them "buckets".

We're going to tell our cuckoo bird to pick up a fruit and place it in one of the buckets. If the bucket is free, the fruit stays there, and we can find it later. However, if the bucket is already occupied, the cuckoo bird will have to move the fruit that is already there to another bucket before placing the new one inside.

This is called the "cuckoo jump", and it continues until we find an empty bucket. Once we have a free spot, we put our fruit in and mark it as present. If we look for a fruit that is not on the list, we will not find it because it was not put in any of the buckets earlier.

Cuckoo filter is a way to check if an item is present in a list or not. By using two buckets and a "cuckoo jump", we can efficiently store and search for items. It is like having a bird helping us out with important tasks!