Varnish

Varnish Cache is a web accelerator also referred to as an HTTP accelerator. You can install it in front of any server that speaks the HTTP protocol and configure it to cache the contents. Varnish Cache is really, really fast and will increase the speed of your web site. One of the key strengths of Varnish Cache is the flexibility of its principal configuration mechanism, VCL, which allows you to define how incoming requests should be dealt with.

Memcached

Memcached is a general-purpose memory object caching system for increasing the speed of dynamic database-driven 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 two-tier architecture. The Memcached distributed memory object caching system is employed by some of the most traffic-intensive sites on the Internet and is supported by popular web applications like Joomla and WordPress.

Node.js

Node.js is a platform for building highly scalable network applications. Built on Chrome's JavaScript runtime, Node.js uses an event-driven, asynchronous input/output model that makes it lightweight and effective, ideal for high-performance content-intensive Internet apps. Node.js uses Google's V8 JavaScript engine, libUV, and several in-built libraries.

InnoDB

InnoDB is the default storage engine for the MySQL open-source database management system. A database engine is the underlying software component that a database management system uses to create, read, modify and delete data from a database. Its latest release features considerable improvements in efficiency, stability and usability. InnoDB offers the standard ACID database transaction attributes, along with declarative referential integrity support. It is included as standard in most binaries distributed by MySQL AB.