This document discusses Twitter's use of various big data technologies to handle its massive scale. It describes how Twitter went from its first tweet to sending over 500 million tweets per day. It then discusses the challenges of supporting a real-time social graph at this scale and how Twitter uses FlockDB and the Gizzard framework to shard and query the social graph distributed across multiple servers. It also explains how Twitter uses Hadoop and Storm to handle batch processing and real-time processing of tweets.