Varnish

Varnish Cache is a web application accelerator also called as a caching HTTP reverse proxy. You can install it in front of any web server that speaks the HTTP protocol and configure it to cache the content. Varnish Cache is very, very fast and will boost your web site's speed. One of the major advantages of Varnish Cache is the flexibility of its configuration language, VCL, which allows you to determine how incoming requests should be dealt with.

Memcached

Memcached is a generic distributed memory object caching system for speeding up dynamic database-powered websites. It is used to lower the number of times an external data source (such as a DB or API) is read by caching data and objects in RAM. The Memcached memory caching system uses a client'server architecture. The Memcached system is used by some of the most frequently visited sites on the web and is supported by popular web applications like Joomla and WordPress.

Node.js

Node.js is a software platform for writing scalable network applications. Built on Chrome's JavaScript runtime, Node.js uses an event-driven, non-blocking input/output model that makes it lightweight and effective, suitable for high-performance content-heavy apps. Node.js uses Google's V8 JavaScript engine, libUV, and a number of built-in libraries.

InnoDB

InnoDB is the default storage engine for the MySQL open-source RDBMS. A storage engine is the principal software component that a DBMS uses to create, read, modify and delete data from a database. The latest edition of InnoDB offers substantial improvements in performance, reliability and functionality. InnoDB offers the standard ACID-compliant transaction properties, as well as declarative referential integrity support. InnoDB is included by default in most binary distributions from MySQL AB.