Varnish

Varnish Cache is a web accelerator also called 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 really, really fast and will improve the speed of your site. One of the important advantages of Varnish Cache is the flexibility of its principal configuration mechanism, VCL, which enables you to define how incoming requests should be handled.

Memcached

Memcached is a generic memory caching system for boosting the load speed of dynamic database-driven sites. 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 distributed memory object caching system uses a client'server architecture. The Memcached distributed memory object caching system is employed by some of the most traffic-intensive web sites on the Internet and is supported by popular CMSs like Joomla and WordPress.

Node.js

Node.js is a platform for writing highly scalable network applications. Written in JavaScript, Node.js uses an event-driven, non-blocking input/output model that makes it lightweight and effective, excellent for high-performance content-heavy network apps. Node.js uses Google's V8 JavaScript engine, libUV, and several in-built libraries.

InnoDB

InnoDB is the default database engine for the MySQL open-source RDBMS. A database engine is the principal software component that a database management system uses to create, read, modify and delete data from a database. The latest release of InnoDB offers considerable improvements in performance, dependability and functionality. InnoDB offers the standard ACID transaction attributes, along with referential integrity support. InnoDB is included as standard in most binary distributions from MySQL AB.