Varnish

Varnish Cache is a web accelerator also famous as a caching HTTP reverse proxy. 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 boost the loading speed of your website. One of the major virtues of Varnish Cache is the flexibility of its principal configuration mechanism, VCL, which enables you to determine how incoming requests should be handled.

Memcached

Memcached is a generic memory caching system for boosting the loading speed of dynamic database-powered web sites. 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 two-tier architecture. The Memcached distributed memory object caching system is employed by some of the most regularly visited websites on the Internet and is supported by popular web applications like Joomla and WordPress.

Node.js

Node.js is a software system for writing highly scalable network applications. Built on Chrome's JavaScript runtime, Node.js uses an event-driven, non-blocking I/O model that makes it lightweight and efficient, ideal for high-performance content-rich network apps. Node.js uses Google's V8 JavaScript engine, libUV, and a number of built-in libraries.

InnoDB

InnoDB is the default database engine for the MySQL open-source DBMS. A database engine is the primary software component that a database management system uses to create, retrieve, modify and delete data from a database. The latest edition of InnoDB offers significant improvements in efficiency, stability and usability. InnoDB offers the standard ACID database transaction features, as well as referential integrity support. It is included by default in most binaries distributed by MySQL AB.