What is there behind Facebook?

 

1.Memcached

This is a distributed memory caching system which Facebook uses a caching layer between the web servers and MySQL servers.

2.HipHop for PHP
 Hip pop converts PHP (Server-side HTML embedded scripting language) into c++ code which can be then be compiled for better performance.And also PHP is used for the front-end.

3.Haystack
This is the Facebook's high performance photo storage/retrieval system.haystack is an object store.Facebook serves around 1.2 million photos per second.And each photo is saved in 4 different resolutions,resulting in more than 80 billion photos.

    4 .Cassandra

    Cassandra is a distributed storage system with no single pint of failure

    5.Scribe

    This is a flexible logging system that Facebook uses for many purposes internally.
  

   6.Erlang

   Used for the chat engine.