Varnish

Varnish Cache is a web application accelerator also famous as an HTTP accelerator. You can install it in front of any web server that speaks HTTP and configure it to cache the contents. Varnish Cache is very, very fast and will boost your site's speed. One of the main strengths of Varnish Cache is the flexibility of its domain-specific language, VCL, which permits you to specify how incoming requests should be tackled.

Memcached

Memcached is a generic distributed memory caching system for boosting the load speed of dynamic database-powered websites. It is used to lower 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 distributed memory object caching system uses a client/server architecture. The Memcached distributed memory caching system is employed by some of the most regularly visited web sites on the World Wide Web and is supported by popular Content Management Systems like Joomla and WordPress.

Node.js

Node.js is a software system for building scalable network apps. Written in JavaScript, Node.js uses an event-driven, non-blocking I/O model that makes it lightweight and efficient, ideal for high-performance content-rich network applications. 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 database engine is the underlying software component that a DBMS uses to create, read, update and delete data from a database. The latest release of InnoDB offers serious improvements in performance, reliability and functionality. InnoDB offers the standard ACID-compliant transaction properties, along with referential integrity support. It is included by default in most binary distributions from MySQL AB.