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 HTTP and configure it to cache the content. Varnish Cache is very, very fast and will increase the speed of your website. One of the key attributes of Varnish Cache is the flexibility of its configuration language, VCL, which enables you to determine how incoming requests should be tackled.

Memcached

Memcached is a general-purpose distributed memory object caching system for boosting the loading speed of 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 memory caching system uses a client'server architecture. The Memcached distributed memory object caching system is used by some of the most traffic-heavy web sites on the Internet and is supported by popular web apps like Joomla and WordPress.

Node.js

Node.js is a software system for building scalable network applications. Built on Chrome's JavaScript runtime, Node.js uses an event-based, non-blocking I/O model that makes it lightweight and efficient, excellent for real-time content-intensive Internet apps. 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 relational database management system. A database engine is the underlying software component that a DBMS uses to create, retrieve, update and delete data from a database. Its latest version offers significant improvements in efficiency, reliability and usability. InnoDB provides the standard ACID-compliant database transaction properties, along with foreign key support. InnoDB is included as standard in most binaries distributed by MySQL AB.