Varnish

Varnish Cache is a web accelerator also known as a caching HTTP reverse proxy. You can install it in front of any web server that speaks HTTP and configure it to cache the content. Varnish Cache is very, very fast and will boost your site's loading speed. One of the important strengths of Varnish Cache is the flexibility of its configuration language, VCL, which allows you to specify how incoming requests should be handled.

Memcached

Memcached is a generic distributed memory caching system for increasing the load speed of dynamic database-driven sites. It is used to decrease the number of times an external data source (such as a database or API) is read by caching data and objects in RAM. The Memcached memory caching system uses a client/server architecture. The Memcached distributed memory caching system is used by some of the most traffic-hungry websites on the Internet and is supported by popular web apps like Joomla and WordPress.

Node.js

Node.js is a platform for building scalable network apps. Built on Chrome's JavaScript runtime, Node.js uses an event-driven, asynchronous input/output model that makes it lightweight and efficient, ideal for real-time content-rich Internet apps. Node.js uses Google's V8 JavaScript engine, libUV, and a number of in-built libraries.

InnoDB

InnoDB is the default storage engine for the MySQL open-source database management system. A storage engine is the principal software component that a database management system uses to create, retrieve, update and delete data from a database. Its latest edition offers significant improvements in performance, dependability and functionality. InnoDB offers the standard ACID-compliant database transaction features, as well as foreign key support. InnoDB is included as standard in most binary distributions from MySQL AB.