caches and messages queues$$that have become fundamental building blocks for services under heavy load.

Memcached is the $$memory cache daemon.$$ It combines the free, idle RAM on the servers on which it is installed into a single, large least$-$recently used $($LRU$)$ cache. Its impact on many large Internet services has been, by all accounts, revolutionary. After glancing at how to use it from Python, I will discuss its implementation, which will teach you about an important modern network concept called sharding.