Varnish

Varnish Cache is a web accelerator also popular as a caching HTTP reverse proxy. You can install it in front of any web server that speaks HTTP and configure it to cache the contents. Varnish Cache is really, really fast and will increase your site's loading speed. One of the main attributes of Varnish Cache is the flexibility of its principal configuration mechanism, VCL, which allows you to choose how incoming requests should be dealt with.

Memcached

Memcached is a general-purpose memory object caching system for boosting the load speed of dynamic database-driven websites. It is used to decrease 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 caching system uses a two-tier architecture. The Memcached memory caching system is used by some of the most popular web sites on the web and is supported by popular CMSs like Joomla and WordPress.

Node.js

Node.js is a software platform for building scalable network apps. Written in JavaScript, Node.js uses an event-driven, asynchronous input/output model that makes it lightweight and effective, perfect for real-time content-heavy Internet 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 RDBMS. A storage engine is the main software component that a database management system uses to create, read, update and delete data from a database. Its latest version features considerable improvements in efficacy, reliability and functionality. InnoDB offers the standard ACID-compliant database transaction attributes, along with foreign key support. It is included as standard in most binary distributions from MySQL AB.