## HyperLogLOg

https://reachtoanil.wordpress.com/2016/08/23/hyperloglog/

## Reservoir sampling

Proof 1 , Explanation  Simple explanation on quora

## Shuffle an array

The general method for shuffling is biased. Check this - https://spin.atomicobject.com/2014/08/11/fisher-yates-shuffle-randomization-algorithm/ and http://www.i-programmer.info/programming/theory/2744-how-not-to-shuffle-the-kunth-fisher-yates-algorithm.html When shuffling the maximum number of possible outcome can't be more then n!( n is the number of items being shuffled). So if the algo generate more then n! possible outcome then the algo is biased. The Knuth Fisher-Yates Algorithm produces unbiased shuffled outcome. It… Continue reading Shuffle an array

## Good to Know Concept

How do giant sites like Facebook & Google check Username or Domain availability, so fast? https://en.wikipedia.org/wiki/Josephus_problem - dynamic prog What is the exact use of a MAC address?  - Youtube

## How the Old Napster Worked – setting up a P2P network.

Link Napster was a mixed Architecture - Client-Server and P2P (Video). Here is what happened when you decided to look for the song: You opened the Napster utility. Napster checked for an Internet connection. If it found a connection, Napster logged you onto the central server. The main purpose of this central server was to… Continue reading How the Old Napster Worked – setting up a P2P network.