Varnish

Varnish Cache is a web accelerator also famous 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 really, really fast and will boost the speed of your web site. One of the important strengths of Varnish Cache is the flexibility of its domain-specific language, VCL, which allows you to specify how incoming requests should be handled.

Memcached

Memcached is a general-purpose memory caching system for boosting the speed of dynamic database-driven websites. It is used to reduce 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 object caching system uses a client'server architecture. The Memcached memory object caching system is employed by some of the most frequently visited websites on the web and is supported by famous web applications like Joomla and WordPress.

Node.js

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

InnoDB

InnoDB is the default storage engine for the MySQL open-source relational database management system. A storage engine is the principal software component that a database management system uses to create, read, modify and delete data from a database. The latest version of InnoDB features significant improvements in performance, reliability and usability. InnoDB offers the standard ACID database transaction attributes, along with declarative referential integrity support. InnoDB is included as standard in most binaries distributed by MySQL AB.