Varnish

Varnish Cache is a web accelerator also referred to as an HTTP accelerator. You can install it in front of any server that speaks HTTP and configure it to cache the contents. Varnish Cache is very, very fast and will boost your website's speed. One of the key virtues of Varnish Cache is the flexibility of its domain-specific language, VCL, which permits you to choose how incoming requests should be dealt with.

Memcached

Memcached is a general-purpose distributed memory caching system for boosting the loading 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 object caching system uses a two-tier architecture. The Memcached memory object caching system is employed by some of the most frequently visited web sites on the web and is supported by famous web applications 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-based, asynchronous I/O model that makes it lightweight and effective, great for high-performance data-rich apps. Node.js uses Google's V8 JavaScript engine, libUV, and several in-built libraries.

InnoDB

InnoDB is the default storage engine for the MySQL open-source database management system. A database engine is the main software component that a database management system uses to create, retrieve, modify and delete data from a database. The latest version of InnoDB offers substantial improvements in efficiency, security and usability. InnoDB offers the standard ACID-compliant transaction attributes, as well as referential integrity support. It is included as standard in most binary distributions from MySQL AB.