Varnish

Varnish Cache is a web accelerator also called 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 contents. Varnish Cache is really, really fast and will boost your website's speed. One of the key virtues of Varnish Cache is the flexibility of its principal configuration mechanism, VCL, which permits you to determine how incoming requests should be dealt with.

Memcached

Memcached is a general-purpose memory caching system for speeding up dynamic database-powered 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 caching system is employed by some of the most traffic-intensive sites on the web and is supported by famous web applications like Joomla and WordPress.

Node.js

Node.js is a software system for writing scalable Internet apps. Written in JavaScript, Node.js uses an event-driven, asynchronous input/output model that makes it lightweight and effective, suitable for high-performance data-heavy Internet 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 RDBMS. A storage engine is the principal software component that a DBMS uses to create, retrieve, modify and delete data from a database. Its latest version features significant improvements in performance, stability and functionality. InnoDB provides the standard ACID database transaction attributes, along with declarative referential integrity support. It is included as standard in most binary distributions from MySQL AB.