Varnish

Varnish Cache is a web accelerator also known as an HTTP accelerator. You can install it in front of any web server that speaks HTTP and configure it to cache the content. Varnish Cache is really, really fast and will boost the loading speed of your web site. One of the key advantages of Varnish Cache is the flexibility of its principal configuration mechanism, VCL, which permits you to determine how incoming requests should be handled.

Memcached

Memcached is a generic memory caching system for increasing the load speed of dynamic database-driven web sites. It is used to decrease 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 client/server architecture. The Memcached distributed memory object caching system is employed by some of the most traffic-hungry web 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 Internet apps. Built on Chrome's JavaScript runtime, Node.js uses an event-driven, non-blocking input/output model that makes it lightweight and efficient, perfect for real-time content-intensive network applications. Node.js uses Google's V8 JavaScript engine, libUV, and a number of in-built libraries.

InnoDB

InnoDB is the default database engine for the MySQL open-source database management system. A storage engine is the primary software component that a database management system uses to create, read, modify and delete data from a database. The latest edition of InnoDB offers considerable improvements in performance, stability and functionality. InnoDB provides the standard ACID-compliant database transaction attributes, along with declarative referential integrity support. It is included by default in most binaries distributed by MySQL AB.